src/java.base/share/classes/java/util/Properties.java
changeset 47216 71c04702a3d5
parent 47008 d0f76f38fb56
child 47423 4fc2a4a29f3d
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/util/Properties.java	Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,1454 @@
+/*
+ * Copyright (c) 1995, 2017, Oracle and/or its affiliates. All rights reserved.
+ * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
+ *
+ * This code is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License version 2 only, as
+ * published by the Free Software Foundation.  Oracle designates this
+ * particular file as subject to the "Classpath" exception as provided
+ * by Oracle in the LICENSE file that accompanied this code.
+ *
+ * This code is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
+ * version 2 for more details (a copy is included in the LICENSE file that
+ * accompanied this code).
+ *
+ * You should have received a copy of the GNU General Public License version
+ * 2 along with this work; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
+ *
+ * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
+ * or visit www.oracle.com if you need additional information or have any
+ * questions.
+ */
+
+package java.util;
+
+import java.io.IOException;
+import java.io.PrintStream;
+import java.io.PrintWriter;
+import java.io.InputStream;
+import java.io.OutputStream;
+import java.io.Reader;
+import java.io.Writer;
+import java.io.OutputStreamWriter;
+import java.io.BufferedWriter;
+import java.io.ObjectInputStream;
+import java.io.ObjectOutputStream;
+import java.io.StreamCorruptedException;
+import java.util.concurrent.ConcurrentHashMap;
+import java.util.function.BiConsumer;
+import java.util.function.BiFunction;
+import java.util.function.Function;
+
+import jdk.internal.util.xml.PropertiesDefaultHandler;
+
+/**
+ * The {@code Properties} class represents a persistent set of
+ * properties. The {@code Properties} can be saved to a stream
+ * or loaded from a stream. Each key and its corresponding value in
+ * the property list is a string.
+ * <p>
+ * A property list can contain another property list as its
+ * "defaults"; this second property list is searched if
+ * the property key is not found in the original property list.
+ * <p>
+ * Because {@code Properties} inherits from {@code Hashtable}, the
+ * {@code put} and {@code putAll} methods can be applied to a
+ * {@code Properties} object.  Their use is strongly discouraged as they
+ * allow the caller to insert entries whose keys or values are not
+ * {@code Strings}.  The {@code setProperty} method should be used
+ * instead.  If the {@code store} or {@code save} method is called
+ * on a "compromised" {@code Properties} object that contains a
+ * non-{@code String} key or value, the call will fail. Similarly,
+ * the call to the {@code propertyNames} or {@code list} method
+ * will fail if it is called on a "compromised" {@code Properties}
+ * object that contains a non-{@code String} key.
+ *
+ * <p>
+ * The iterators returned by the {@code iterator} method of this class's
+ * "collection views" (that is, {@code entrySet()}, {@code keySet()}, and
+ * {@code values()}) may not fail-fast (unlike the Hashtable implementation).
+ * These iterators are guaranteed to traverse elements as they existed upon
+ * construction exactly once, and may (but are not guaranteed to) reflect any
+ * modifications subsequent to construction.
+ * <p>
+ * The {@link #load(java.io.Reader) load(Reader)} {@code /}
+ * {@link #store(java.io.Writer, java.lang.String) store(Writer, String)}
+ * methods load and store properties from and to a character based stream
+ * in a simple line-oriented format specified below.
+ *
+ * The {@link #load(java.io.InputStream) load(InputStream)} {@code /}
+ * {@link #store(java.io.OutputStream, java.lang.String) store(OutputStream, String)}
+ * methods work the same way as the load(Reader)/store(Writer, String) pair, except
+ * the input/output stream is encoded in ISO 8859-1 character encoding.
+ * Characters that cannot be directly represented in this encoding can be written using
+ * Unicode escapes as defined in section 3.3 of
+ * <cite>The Java&trade; Language Specification</cite>;
+ * only a single 'u' character is allowed in an escape
+ * sequence.
+ *
+ * <p> The {@link #loadFromXML(InputStream)} and {@link
+ * #storeToXML(OutputStream, String, String)} methods load and store properties
+ * in a simple XML format.  By default the UTF-8 character encoding is used,
+ * however a specific encoding may be specified if required. Implementations
+ * are required to support UTF-8 and UTF-16 and may support other encodings.
+ * An XML properties document has the following DOCTYPE declaration:
+ *
+ * <pre>
+ * &lt;!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"&gt;
+ * </pre>
+ * Note that the system URI (http://java.sun.com/dtd/properties.dtd) is
+ * <i>not</i> accessed when exporting or importing properties; it merely
+ * serves as a string to uniquely identify the DTD, which is:
+ * <pre>
+ *    &lt;?xml version="1.0" encoding="UTF-8"?&gt;
+ *
+ *    &lt;!-- DTD for properties --&gt;
+ *
+ *    &lt;!ELEMENT properties ( comment?, entry* ) &gt;
+ *
+ *    &lt;!ATTLIST properties version CDATA #FIXED "1.0"&gt;
+ *
+ *    &lt;!ELEMENT comment (#PCDATA) &gt;
+ *
+ *    &lt;!ELEMENT entry (#PCDATA) &gt;
+ *
+ *    &lt;!ATTLIST entry key CDATA #REQUIRED&gt;
+ * </pre>
+ *
+ * <p>This class is thread-safe: multiple threads can share a single
+ * {@code Properties} object without the need for external synchronization.
+ *
+ * @author  Arthur van Hoff
+ * @author  Michael McCloskey
+ * @author  Xueming Shen
+ * @since   1.0
+ */
+public
+class Properties extends Hashtable<Object,Object> {
+    /**
+     * use serialVersionUID from JDK 1.1.X for interoperability
+     */
+     private static final long serialVersionUID = 4112578634029874840L;
+
+    /**
+     * A property list that contains default values for any keys not
+     * found in this property list.
+     *
+     * @serial
+     */
+    protected Properties defaults;
+
+    /**
+     * Properties does not store values in its inherited Hashtable, but instead
+     * in an internal ConcurrentHashMap.  Synchronization is omitted from
+     * simple read operations.  Writes and bulk operations remain synchronized,
+     * as in Hashtable.
+     */
+    private transient ConcurrentHashMap<Object, Object> map =
+            new ConcurrentHashMap<>(8);
+
+    /**
+     * Creates an empty property list with no default values.
+     */
+    public Properties() {
+        this(null);
+    }
+
+    /**
+     * Creates an empty property list with the specified defaults.
+     *
+     * @param   defaults   the defaults.
+     */
+    public Properties(Properties defaults) {
+        // use package-private constructor to
+        // initialize unused fields with dummy values
+        super((Void) null);
+        this.defaults = defaults;
+    }
+
+    /**
+     * Calls the {@code Hashtable} method {@code put}. Provided for
+     * parallelism with the {@code getProperty} method. Enforces use of
+     * strings for property keys and values. The value returned is the
+     * result of the {@code Hashtable} call to {@code put}.
+     *
+     * @param key the key to be placed into this property list.
+     * @param value the value corresponding to {@code key}.
+     * @return     the previous value of the specified key in this property
+     *             list, or {@code null} if it did not have one.
+     * @see #getProperty
+     * @since    1.2
+     */
+    public synchronized Object setProperty(String key, String value) {
+        return put(key, value);
+    }
+
+
+    /**
+     * Reads a property list (key and element pairs) from the input
+     * character stream in a simple line-oriented format.
+     * <p>
+     * Properties are processed in terms of lines. There are two
+     * kinds of line, <i>natural lines</i> and <i>logical lines</i>.
+     * A natural line is defined as a line of
+     * characters that is terminated either by a set of line terminator
+     * characters ({@code \n} or {@code \r} or {@code \r\n})
+     * or by the end of the stream. A natural line may be either a blank line,
+     * a comment line, or hold all or some of a key-element pair. A logical
+     * line holds all the data of a key-element pair, which may be spread
+     * out across several adjacent natural lines by escaping
+     * the line terminator sequence with a backslash character
+     * {@code \}.  Note that a comment line cannot be extended
+     * in this manner; every natural line that is a comment must have
+     * its own comment indicator, as described below. Lines are read from
+     * input until the end of the stream is reached.
+     *
+     * <p>
+     * A natural line that contains only white space characters is
+     * considered blank and is ignored.  A comment line has an ASCII
+     * {@code '#'} or {@code '!'} as its first non-white
+     * space character; comment lines are also ignored and do not
+     * encode key-element information.  In addition to line
+     * terminators, this format considers the characters space
+     * ({@code ' '}, {@code '\u005Cu0020'}), tab
+     * ({@code '\t'}, {@code '\u005Cu0009'}), and form feed
+     * ({@code '\f'}, {@code '\u005Cu000C'}) to be white
+     * space.
+     *
+     * <p>
+     * If a logical line is spread across several natural lines, the
+     * backslash escaping the line terminator sequence, the line
+     * terminator sequence, and any white space at the start of the
+     * following line have no affect on the key or element values.
+     * The remainder of the discussion of key and element parsing
+     * (when loading) will assume all the characters constituting
+     * the key and element appear on a single natural line after
+     * line continuation characters have been removed.  Note that
+     * it is <i>not</i> sufficient to only examine the character
+     * preceding a line terminator sequence to decide if the line
+     * terminator is escaped; there must be an odd number of
+     * contiguous backslashes for the line terminator to be escaped.
+     * Since the input is processed from left to right, a
+     * non-zero even number of 2<i>n</i> contiguous backslashes
+     * before a line terminator (or elsewhere) encodes <i>n</i>
+     * backslashes after escape processing.
+     *
+     * <p>
+     * The key contains all of the characters in the line starting
+     * with the first non-white space character and up to, but not
+     * including, the first unescaped {@code '='},
+     * {@code ':'}, or white space character other than a line
+     * terminator. All of these key termination characters may be
+     * included in the key by escaping them with a preceding backslash
+     * character; for example,<p>
+     *
+     * {@code \:\=}<p>
+     *
+     * would be the two-character key {@code ":="}.  Line
+     * terminator characters can be included using {@code \r} and
+     * {@code \n} escape sequences.  Any white space after the
+     * key is skipped; if the first non-white space character after
+     * the key is {@code '='} or {@code ':'}, then it is
+     * ignored and any white space characters after it are also
+     * skipped.  All remaining characters on the line become part of
+     * the associated element string; if there are no remaining
+     * characters, the element is the empty string
+     * {@code ""}.  Once the raw character sequences
+     * constituting the key and element are identified, escape
+     * processing is performed as described above.
+     *
+     * <p>
+     * As an example, each of the following three lines specifies the key
+     * {@code "Truth"} and the associated element value
+     * {@code "Beauty"}:
+     * <pre>
+     * Truth = Beauty
+     *  Truth:Beauty
+     * Truth                    :Beauty
+     * </pre>
+     * As another example, the following three lines specify a single
+     * property:
+     * <pre>
+     * fruits                           apple, banana, pear, \
+     *                                  cantaloupe, watermelon, \
+     *                                  kiwi, mango
+     * </pre>
+     * The key is {@code "fruits"} and the associated element is:
+     * <pre>"apple, banana, pear, cantaloupe, watermelon, kiwi, mango"</pre>
+     * Note that a space appears before each {@code \} so that a space
+     * will appear after each comma in the final result; the {@code \},
+     * line terminator, and leading white space on the continuation line are
+     * merely discarded and are <i>not</i> replaced by one or more other
+     * characters.
+     * <p>
+     * As a third example, the line:
+     * <pre>cheeses
+     * </pre>
+     * specifies that the key is {@code "cheeses"} and the associated
+     * element is the empty string {@code ""}.
+     * <p>
+     * <a id="unicodeescapes"></a>
+     * Characters in keys and elements can be represented in escape
+     * sequences similar to those used for character and string literals
+     * (see sections 3.3 and 3.10.6 of
+     * <cite>The Java&trade; Language Specification</cite>).
+     *
+     * The differences from the character escape sequences and Unicode
+     * escapes used for characters and strings are:
+     *
+     * <ul>
+     * <li> Octal escapes are not recognized.
+     *
+     * <li> The character sequence {@code \b} does <i>not</i>
+     * represent a backspace character.
+     *
+     * <li> The method does not treat a backslash character,
+     * {@code \}, before a non-valid escape character as an
+     * error; the backslash is silently dropped.  For example, in a
+     * Java string the sequence {@code "\z"} would cause a
+     * compile time error.  In contrast, this method silently drops
+     * the backslash.  Therefore, this method treats the two character
+     * sequence {@code "\b"} as equivalent to the single
+     * character {@code 'b'}.
+     *
+     * <li> Escapes are not necessary for single and double quotes;
+     * however, by the rule above, single and double quote characters
+     * preceded by a backslash still yield single and double quote
+     * characters, respectively.
+     *
+     * <li> Only a single 'u' character is allowed in a Unicode escape
+     * sequence.
+     *
+     * </ul>
+     * <p>
+     * The specified stream remains open after this method returns.
+     *
+     * @param   reader   the input character stream.
+     * @throws  IOException  if an error occurred when reading from the
+     *          input stream.
+     * @throws  IllegalArgumentException if a malformed Unicode escape
+     *          appears in the input.
+     * @throws  NullPointerException if {@code reader} is null.
+     * @since   1.6
+     */
+    public synchronized void load(Reader reader) throws IOException {
+        Objects.requireNonNull(reader, "reader parameter is null");
+        load0(new LineReader(reader));
+    }
+
+    /**
+     * Reads a property list (key and element pairs) from the input
+     * byte stream. The input stream is in a simple line-oriented
+     * format as specified in
+     * {@link #load(java.io.Reader) load(Reader)} and is assumed to use
+     * the ISO 8859-1 character encoding; that is each byte is one Latin1
+     * character. Characters not in Latin1, and certain special characters,
+     * are represented in keys and elements using Unicode escapes as defined in
+     * section 3.3 of
+     * <cite>The Java&trade; Language Specification</cite>.
+     * <p>
+     * The specified stream remains open after this method returns.
+     *
+     * @param      inStream   the input stream.
+     * @exception  IOException  if an error occurred when reading from the
+     *             input stream.
+     * @throws     IllegalArgumentException if the input stream contains a
+     *             malformed Unicode escape sequence.
+     * @throws     NullPointerException if {@code inStream} is null.
+     * @since 1.2
+     */
+    public synchronized void load(InputStream inStream) throws IOException {
+        Objects.requireNonNull(inStream, "inStream parameter is null");
+        load0(new LineReader(inStream));
+    }
+
+    private void load0 (LineReader lr) throws IOException {
+        char[] convtBuf = new char[1024];
+        int limit;
+        int keyLen;
+        int valueStart;
+        char c;
+        boolean hasSep;
+        boolean precedingBackslash;
+
+        while ((limit = lr.readLine()) >= 0) {
+            c = 0;
+            keyLen = 0;
+            valueStart = limit;
+            hasSep = false;
+
+            //System.out.println("line=<" + new String(lineBuf, 0, limit) + ">");
+            precedingBackslash = false;
+            while (keyLen < limit) {
+                c = lr.lineBuf[keyLen];
+                //need check if escaped.
+                if ((c == '=' ||  c == ':') && !precedingBackslash) {
+                    valueStart = keyLen + 1;
+                    hasSep = true;
+                    break;
+                } else if ((c == ' ' || c == '\t' ||  c == '\f') && !precedingBackslash) {
+                    valueStart = keyLen + 1;
+                    break;
+                }
+                if (c == '\\') {
+                    precedingBackslash = !precedingBackslash;
+                } else {
+                    precedingBackslash = false;
+                }
+                keyLen++;
+            }
+            while (valueStart < limit) {
+                c = lr.lineBuf[valueStart];
+                if (c != ' ' && c != '\t' &&  c != '\f') {
+                    if (!hasSep && (c == '=' ||  c == ':')) {
+                        hasSep = true;
+                    } else {
+                        break;
+                    }
+                }
+                valueStart++;
+            }
+            String key = loadConvert(lr.lineBuf, 0, keyLen, convtBuf);
+            String value = loadConvert(lr.lineBuf, valueStart, limit - valueStart, convtBuf);
+            put(key, value);
+        }
+    }
+
+    /* Read in a "logical line" from an InputStream/Reader, skip all comment
+     * and blank lines and filter out those leading whitespace characters
+     * (\u0020, \u0009 and \u000c) from the beginning of a "natural line".
+     * Method returns the char length of the "logical line" and stores
+     * the line in "lineBuf".
+     */
+    class LineReader {
+        public LineReader(InputStream inStream) {
+            this.inStream = inStream;
+            inByteBuf = new byte[8192];
+        }
+
+        public LineReader(Reader reader) {
+            this.reader = reader;
+            inCharBuf = new char[8192];
+        }
+
+        byte[] inByteBuf;
+        char[] inCharBuf;
+        char[] lineBuf = new char[1024];
+        int inLimit = 0;
+        int inOff = 0;
+        InputStream inStream;
+        Reader reader;
+
+        int readLine() throws IOException {
+            int len = 0;
+            char c = 0;
+
+            boolean skipWhiteSpace = true;
+            boolean isCommentLine = false;
+            boolean isNewLine = true;
+            boolean appendedLineBegin = false;
+            boolean precedingBackslash = false;
+            boolean skipLF = false;
+
+            while (true) {
+                if (inOff >= inLimit) {
+                    inLimit = (inStream==null)?reader.read(inCharBuf)
+                                              :inStream.read(inByteBuf);
+                    inOff = 0;
+                    if (inLimit <= 0) {
+                        if (len == 0 || isCommentLine) {
+                            return -1;
+                        }
+                        if (precedingBackslash) {
+                            len--;
+                        }
+                        return len;
+                    }
+                }
+                if (inStream != null) {
+                    //The line below is equivalent to calling a
+                    //ISO8859-1 decoder.
+                    c = (char)(inByteBuf[inOff++] & 0xFF);
+                } else {
+                    c = inCharBuf[inOff++];
+                }
+                if (skipLF) {
+                    skipLF = false;
+                    if (c == '\n') {
+                        continue;
+                    }
+                }
+                if (skipWhiteSpace) {
+                    if (c == ' ' || c == '\t' || c == '\f') {
+                        continue;
+                    }
+                    if (!appendedLineBegin && (c == '\r' || c == '\n')) {
+                        continue;
+                    }
+                    skipWhiteSpace = false;
+                    appendedLineBegin = false;
+                }
+                if (isNewLine) {
+                    isNewLine = false;
+                    if (c == '#' || c == '!') {
+                        // Comment, quickly consume the rest of the line,
+                        // resume on line-break and backslash.
+                        if (inStream != null) {
+                            while (inOff < inLimit) {
+                                byte b = inByteBuf[inOff++];
+                                if (b == '\n' || b == '\r' || b == '\\') {
+                                    c = (char)(b & 0xFF);
+                                    break;
+                                }
+                            }
+                        } else {
+                            while (inOff < inLimit) {
+                                c = inCharBuf[inOff++];
+                                if (c == '\n' || c == '\r' || c == '\\') {
+                                    break;
+                                }
+                            }
+                        }
+                        isCommentLine = true;
+                    }
+                }
+
+                if (c != '\n' && c != '\r') {
+                    lineBuf[len++] = c;
+                    if (len == lineBuf.length) {
+                        int newLength = lineBuf.length * 2;
+                        if (newLength < 0) {
+                            newLength = Integer.MAX_VALUE;
+                        }
+                        char[] buf = new char[newLength];
+                        System.arraycopy(lineBuf, 0, buf, 0, lineBuf.length);
+                        lineBuf = buf;
+                    }
+                    //flip the preceding backslash flag
+                    if (c == '\\') {
+                        precedingBackslash = !precedingBackslash;
+                    } else {
+                        precedingBackslash = false;
+                    }
+                }
+                else {
+                    // reached EOL
+                    if (isCommentLine || len == 0) {
+                        isCommentLine = false;
+                        isNewLine = true;
+                        skipWhiteSpace = true;
+                        len = 0;
+                        continue;
+                    }
+                    if (inOff >= inLimit) {
+                        inLimit = (inStream==null)
+                                  ?reader.read(inCharBuf)
+                                  :inStream.read(inByteBuf);
+                        inOff = 0;
+                        if (inLimit <= 0) {
+                            if (precedingBackslash) {
+                                len--;
+                            }
+                            return len;
+                        }
+                    }
+                    if (precedingBackslash) {
+                        len -= 1;
+                        //skip the leading whitespace characters in following line
+                        skipWhiteSpace = true;
+                        appendedLineBegin = true;
+                        precedingBackslash = false;
+                        if (c == '\r') {
+                            skipLF = true;
+                        }
+                    } else {
+                        return len;
+                    }
+                }
+            }
+        }
+    }
+
+    /*
+     * Converts encoded &#92;uxxxx to unicode chars
+     * and changes special saved chars to their original forms
+     */
+    private String loadConvert (char[] in, int off, int len, char[] convtBuf) {
+        if (convtBuf.length < len) {
+            int newLen = len * 2;
+            if (newLen < 0) {
+                newLen = Integer.MAX_VALUE;
+            }
+            convtBuf = new char[newLen];
+        }
+        char aChar;
+        char[] out = convtBuf;
+        int outLen = 0;
+        int end = off + len;
+
+        while (off < end) {
+            aChar = in[off++];
+            if (aChar == '\\') {
+                aChar = in[off++];
+                if(aChar == 'u') {
+                    // Read the xxxx
+                    int value=0;
+                    for (int i=0; i<4; i++) {
+                        aChar = in[off++];
+                        switch (aChar) {
+                          case '0': case '1': case '2': case '3': case '4':
+                          case '5': case '6': case '7': case '8': case '9':
+                             value = (value << 4) + aChar - '0';
+                             break;
+                          case 'a': case 'b': case 'c':
+                          case 'd': case 'e': case 'f':
+                             value = (value << 4) + 10 + aChar - 'a';
+                             break;
+                          case 'A': case 'B': case 'C':
+                          case 'D': case 'E': case 'F':
+                             value = (value << 4) + 10 + aChar - 'A';
+                             break;
+                          default:
+                              throw new IllegalArgumentException(
+                                           "Malformed \\uxxxx encoding.");
+                        }
+                     }
+                    out[outLen++] = (char)value;
+                } else {
+                    if (aChar == 't') aChar = '\t';
+                    else if (aChar == 'r') aChar = '\r';
+                    else if (aChar == 'n') aChar = '\n';
+                    else if (aChar == 'f') aChar = '\f';
+                    out[outLen++] = aChar;
+                }
+            } else {
+                out[outLen++] = aChar;
+            }
+        }
+        return new String (out, 0, outLen);
+    }
+
+    /*
+     * Converts unicodes to encoded &#92;uxxxx and escapes
+     * special characters with a preceding slash
+     */
+    private String saveConvert(String theString,
+                               boolean escapeSpace,
+                               boolean escapeUnicode) {
+        int len = theString.length();
+        int bufLen = len * 2;
+        if (bufLen < 0) {
+            bufLen = Integer.MAX_VALUE;
+        }
+        StringBuilder outBuffer = new StringBuilder(bufLen);
+
+        for(int x=0; x<len; x++) {
+            char aChar = theString.charAt(x);
+            // Handle common case first, selecting largest block that
+            // avoids the specials below
+            if ((aChar > 61) && (aChar < 127)) {
+                if (aChar == '\\') {
+                    outBuffer.append('\\'); outBuffer.append('\\');
+                    continue;
+                }
+                outBuffer.append(aChar);
+                continue;
+            }
+            switch(aChar) {
+                case ' ':
+                    if (x == 0 || escapeSpace)
+                        outBuffer.append('\\');
+                    outBuffer.append(' ');
+                    break;
+                case '\t':outBuffer.append('\\'); outBuffer.append('t');
+                          break;
+                case '\n':outBuffer.append('\\'); outBuffer.append('n');
+                          break;
+                case '\r':outBuffer.append('\\'); outBuffer.append('r');
+                          break;
+                case '\f':outBuffer.append('\\'); outBuffer.append('f');
+                          break;
+                case '=': // Fall through
+                case ':': // Fall through
+                case '#': // Fall through
+                case '!':
+                    outBuffer.append('\\'); outBuffer.append(aChar);
+                    break;
+                default:
+                    if (((aChar < 0x0020) || (aChar > 0x007e)) & escapeUnicode ) {
+                        outBuffer.append('\\');
+                        outBuffer.append('u');
+                        outBuffer.append(toHex((aChar >> 12) & 0xF));
+                        outBuffer.append(toHex((aChar >>  8) & 0xF));
+                        outBuffer.append(toHex((aChar >>  4) & 0xF));
+                        outBuffer.append(toHex( aChar        & 0xF));
+                    } else {
+                        outBuffer.append(aChar);
+                    }
+            }
+        }
+        return outBuffer.toString();
+    }
+
+    private static void writeComments(BufferedWriter bw, String comments)
+        throws IOException {
+        bw.write("#");
+        int len = comments.length();
+        int current = 0;
+        int last = 0;
+        char[] uu = new char[6];
+        uu[0] = '\\';
+        uu[1] = 'u';
+        while (current < len) {
+            char c = comments.charAt(current);
+            if (c > '\u00ff' || c == '\n' || c == '\r') {
+                if (last != current)
+                    bw.write(comments.substring(last, current));
+                if (c > '\u00ff') {
+                    uu[2] = toHex((c >> 12) & 0xf);
+                    uu[3] = toHex((c >>  8) & 0xf);
+                    uu[4] = toHex((c >>  4) & 0xf);
+                    uu[5] = toHex( c        & 0xf);
+                    bw.write(new String(uu));
+                } else {
+                    bw.newLine();
+                    if (c == '\r' &&
+                        current != len - 1 &&
+                        comments.charAt(current + 1) == '\n') {
+                        current++;
+                    }
+                    if (current == len - 1 ||
+                        (comments.charAt(current + 1) != '#' &&
+                        comments.charAt(current + 1) != '!'))
+                        bw.write("#");
+                }
+                last = current + 1;
+            }
+            current++;
+        }
+        if (last != current)
+            bw.write(comments.substring(last, current));
+        bw.newLine();
+    }
+
+    /**
+     * Calls the {@code store(OutputStream out, String comments)} method
+     * and suppresses IOExceptions that were thrown.
+     *
+     * @deprecated This method does not throw an IOException if an I/O error
+     * occurs while saving the property list.  The preferred way to save a
+     * properties list is via the {@code store(OutputStream out,
+     * String comments)} method or the
+     * {@code storeToXML(OutputStream os, String comment)} method.
+     *
+     * @param   out      an output stream.
+     * @param   comments   a description of the property list.
+     * @exception  ClassCastException  if this {@code Properties} object
+     *             contains any keys or values that are not
+     *             {@code Strings}.
+     */
+    @Deprecated
+    public void save(OutputStream out, String comments)  {
+        try {
+            store(out, comments);
+        } catch (IOException e) {
+        }
+    }
+
+    /**
+     * Writes this property list (key and element pairs) in this
+     * {@code Properties} table to the output character stream in a
+     * format suitable for using the {@link #load(java.io.Reader) load(Reader)}
+     * method.
+     * <p>
+     * Properties from the defaults table of this {@code Properties}
+     * table (if any) are <i>not</i> written out by this method.
+     * <p>
+     * If the comments argument is not null, then an ASCII {@code #}
+     * character, the comments string, and a line separator are first written
+     * to the output stream. Thus, the {@code comments} can serve as an
+     * identifying comment. Any one of a line feed ('\n'), a carriage
+     * return ('\r'), or a carriage return followed immediately by a line feed
+     * in comments is replaced by a line separator generated by the {@code Writer}
+     * and if the next character in comments is not character {@code #} or
+     * character {@code !} then an ASCII {@code #} is written out
+     * after that line separator.
+     * <p>
+     * Next, a comment line is always written, consisting of an ASCII
+     * {@code #} character, the current date and time (as if produced
+     * by the {@code toString} method of {@code Date} for the
+     * current time), and a line separator as generated by the {@code Writer}.
+     * <p>
+     * Then every entry in this {@code Properties} table is
+     * written out, one per line. For each entry the key string is
+     * written, then an ASCII {@code =}, then the associated
+     * element string. For the key, all space characters are
+     * written with a preceding {@code \} character.  For the
+     * element, leading space characters, but not embedded or trailing
+     * space characters, are written with a preceding {@code \}
+     * character. The key and element characters {@code #},
+     * {@code !}, {@code =}, and {@code :} are written
+     * with a preceding backslash to ensure that they are properly loaded.
+     * <p>
+     * After the entries have been written, the output stream is flushed.
+     * The output stream remains open after this method returns.
+     *
+     * @param   writer      an output character stream writer.
+     * @param   comments   a description of the property list.
+     * @exception  IOException if writing this property list to the specified
+     *             output stream throws an {@code IOException}.
+     * @exception  ClassCastException  if this {@code Properties} object
+     *             contains any keys or values that are not {@code Strings}.
+     * @exception  NullPointerException  if {@code writer} is null.
+     * @since 1.6
+     */
+    public void store(Writer writer, String comments)
+        throws IOException
+    {
+        store0((writer instanceof BufferedWriter)?(BufferedWriter)writer
+                                                 : new BufferedWriter(writer),
+               comments,
+               false);
+    }
+
+    /**
+     * Writes this property list (key and element pairs) in this
+     * {@code Properties} table to the output stream in a format suitable
+     * for loading into a {@code Properties} table using the
+     * {@link #load(InputStream) load(InputStream)} method.
+     * <p>
+     * Properties from the defaults table of this {@code Properties}
+     * table (if any) are <i>not</i> written out by this method.
+     * <p>
+     * This method outputs the comments, properties keys and values in
+     * the same format as specified in
+     * {@link #store(java.io.Writer, java.lang.String) store(Writer)},
+     * with the following differences:
+     * <ul>
+     * <li>The stream is written using the ISO 8859-1 character encoding.
+     *
+     * <li>Characters not in Latin-1 in the comments are written as
+     * {@code \u005Cu}<i>xxxx</i> for their appropriate unicode
+     * hexadecimal value <i>xxxx</i>.
+     *
+     * <li>Characters less than {@code \u005Cu0020} and characters greater
+     * than {@code \u005Cu007E} in property keys or values are written
+     * as {@code \u005Cu}<i>xxxx</i> for the appropriate hexadecimal
+     * value <i>xxxx</i>.
+     * </ul>
+     * <p>
+     * After the entries have been written, the output stream is flushed.
+     * The output stream remains open after this method returns.
+     *
+     * @param   out      an output stream.
+     * @param   comments   a description of the property list.
+     * @exception  IOException if writing this property list to the specified
+     *             output stream throws an {@code IOException}.
+     * @exception  ClassCastException  if this {@code Properties} object
+     *             contains any keys or values that are not {@code Strings}.
+     * @exception  NullPointerException  if {@code out} is null.
+     * @since 1.2
+     */
+    public void store(OutputStream out, String comments)
+        throws IOException
+    {
+        store0(new BufferedWriter(new OutputStreamWriter(out, "8859_1")),
+               comments,
+               true);
+    }
+
+    private void store0(BufferedWriter bw, String comments, boolean escUnicode)
+        throws IOException
+    {
+        if (comments != null) {
+            writeComments(bw, comments);
+        }
+        bw.write("#" + new Date().toString());
+        bw.newLine();
+        synchronized (this) {
+            for (Map.Entry<Object, Object> e : entrySet()) {
+                String key = (String)e.getKey();
+                String val = (String)e.getValue();
+                key = saveConvert(key, true, escUnicode);
+                /* No need to escape embedded and trailing spaces for value, hence
+                 * pass false to flag.
+                 */
+                val = saveConvert(val, false, escUnicode);
+                bw.write(key + "=" + val);
+                bw.newLine();
+            }
+        }
+        bw.flush();
+    }
+
+    /**
+     * Loads all of the properties represented by the XML document on the
+     * specified input stream into this properties table.
+     *
+     * <p>The XML document must have the following DOCTYPE declaration:
+     * <pre>
+     * &lt;!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"&gt;
+     * </pre>
+     * Furthermore, the document must satisfy the properties DTD described
+     * above.
+     *
+     * <p> An implementation is required to read XML documents that use the
+     * "{@code UTF-8}" or "{@code UTF-16}" encoding. An implementation may
+     * support additional encodings.
+     *
+     * <p>The specified stream is closed after this method returns.
+     *
+     * @param in the input stream from which to read the XML document.
+     * @throws IOException if reading from the specified input stream
+     *         results in an {@code IOException}.
+     * @throws java.io.UnsupportedEncodingException if the document's encoding
+     *         declaration can be read and it specifies an encoding that is not
+     *         supported
+     * @throws InvalidPropertiesFormatException Data on input stream does not
+     *         constitute a valid XML document with the mandated document type.
+     * @throws NullPointerException if {@code in} is null.
+     * @see    #storeToXML(OutputStream, String, String)
+     * @see    <a href="http://www.w3.org/TR/REC-xml/#charencoding">Character
+     *         Encoding in Entities</a>
+     * @since 1.5
+     */
+    public synchronized void loadFromXML(InputStream in)
+        throws IOException, InvalidPropertiesFormatException
+    {
+        Objects.requireNonNull(in);
+        PropertiesDefaultHandler handler = new PropertiesDefaultHandler();
+        handler.load(this, in);
+        in.close();
+    }
+
+    /**
+     * Emits an XML document representing all of the properties contained
+     * in this table.
+     *
+     * <p> An invocation of this method of the form {@code props.storeToXML(os,
+     * comment)} behaves in exactly the same way as the invocation
+     * {@code props.storeToXML(os, comment, "UTF-8");}.
+     *
+     * @param os the output stream on which to emit the XML document.
+     * @param comment a description of the property list, or {@code null}
+     *        if no comment is desired.
+     * @throws IOException if writing to the specified output stream
+     *         results in an {@code IOException}.
+     * @throws NullPointerException if {@code os} is null.
+     * @throws ClassCastException  if this {@code Properties} object
+     *         contains any keys or values that are not
+     *         {@code Strings}.
+     * @see    #loadFromXML(InputStream)
+     * @since 1.5
+     */
+    public void storeToXML(OutputStream os, String comment)
+        throws IOException
+    {
+        storeToXML(os, comment, "UTF-8");
+    }
+
+    /**
+     * Emits an XML document representing all of the properties contained
+     * in this table, using the specified encoding.
+     *
+     * <p>The XML document will have the following DOCTYPE declaration:
+     * <pre>
+     * &lt;!DOCTYPE properties SYSTEM "http://java.sun.com/dtd/properties.dtd"&gt;
+     * </pre>
+     *
+     * <p>If the specified comment is {@code null} then no comment
+     * will be stored in the document.
+     *
+     * <p> An implementation is required to support writing of XML documents
+     * that use the "{@code UTF-8}" or "{@code UTF-16}" encoding. An
+     * implementation may support additional encodings.
+     *
+     * <p>The specified stream remains open after this method returns.
+     *
+     * @param os        the output stream on which to emit the XML document.
+     * @param comment   a description of the property list, or {@code null}
+     *                  if no comment is desired.
+     * @param  encoding the name of a supported
+     *                  <a href="../lang/package-summary.html#charenc">
+     *                  character encoding</a>
+     *
+     * @throws IOException if writing to the specified output stream
+     *         results in an {@code IOException}.
+     * @throws java.io.UnsupportedEncodingException if the encoding is not
+     *         supported by the implementation.
+     * @throws NullPointerException if {@code os} is {@code null},
+     *         or if {@code encoding} is {@code null}.
+     * @throws ClassCastException  if this {@code Properties} object
+     *         contains any keys or values that are not
+     *         {@code Strings}.
+     * @see    #loadFromXML(InputStream)
+     * @see    <a href="http://www.w3.org/TR/REC-xml/#charencoding">Character
+     *         Encoding in Entities</a>
+     * @since 1.5
+     */
+    public void storeToXML(OutputStream os, String comment, String encoding)
+        throws IOException
+    {
+        Objects.requireNonNull(os);
+        Objects.requireNonNull(encoding);
+        PropertiesDefaultHandler handler = new PropertiesDefaultHandler();
+        handler.store(this, os, comment, encoding);
+    }
+
+    /**
+     * Searches for the property with the specified key in this property list.
+     * If the key is not found in this property list, the default property list,
+     * and its defaults, recursively, are then checked. The method returns
+     * {@code null} if the property is not found.
+     *
+     * @param   key   the property key.
+     * @return  the value in this property list with the specified key value.
+     * @see     #setProperty
+     * @see     #defaults
+     */
+    public String getProperty(String key) {
+        Object oval = map.get(key);
+        String sval = (oval instanceof String) ? (String)oval : null;
+        return ((sval == null) && (defaults != null)) ? defaults.getProperty(key) : sval;
+    }
+
+    /**
+     * Searches for the property with the specified key in this property list.
+     * If the key is not found in this property list, the default property list,
+     * and its defaults, recursively, are then checked. The method returns the
+     * default value argument if the property is not found.
+     *
+     * @param   key            the hashtable key.
+     * @param   defaultValue   a default value.
+     *
+     * @return  the value in this property list with the specified key value.
+     * @see     #setProperty
+     * @see     #defaults
+     */
+    public String getProperty(String key, String defaultValue) {
+        String val = getProperty(key);
+        return (val == null) ? defaultValue : val;
+    }
+
+    /**
+     * Returns an enumeration of all the keys in this property list,
+     * including distinct keys in the default property list if a key
+     * of the same name has not already been found from the main
+     * properties list.
+     *
+     * @return  an enumeration of all the keys in this property list, including
+     *          the keys in the default property list.
+     * @throws  ClassCastException if any key in this property list
+     *          is not a string.
+     * @see     java.util.Enumeration
+     * @see     java.util.Properties#defaults
+     * @see     #stringPropertyNames
+     */
+    public Enumeration<?> propertyNames() {
+        Hashtable<String,Object> h = new Hashtable<>();
+        enumerate(h);
+        return h.keys();
+    }
+
+    /**
+     * Returns an unmodifiable set of keys from this property list
+     * where the key and its corresponding value are strings,
+     * including distinct keys in the default property list if a key
+     * of the same name has not already been found from the main
+     * properties list.  Properties whose key or value is not
+     * of type {@code String} are omitted.
+     * <p>
+     * The returned set is not backed by this {@code Properties} object.
+     * Changes to this {@code Properties} object are not reflected in the
+     * returned set.
+     *
+     * @return  an unmodifiable set of keys in this property list where
+     *          the key and its corresponding value are strings,
+     *          including the keys in the default property list.
+     * @see     java.util.Properties#defaults
+     * @since   1.6
+     */
+    public Set<String> stringPropertyNames() {
+        Map<String, String> h = new HashMap<>();
+        enumerateStringProperties(h);
+        return Collections.unmodifiableSet(h.keySet());
+    }
+
+    /**
+     * Prints this property list out to the specified output stream.
+     * This method is useful for debugging.
+     *
+     * @param   out   an output stream.
+     * @throws  ClassCastException if any key in this property list
+     *          is not a string.
+     */
+    public void list(PrintStream out) {
+        out.println("-- listing properties --");
+        Map<String, Object> h = new HashMap<>();
+        enumerate(h);
+        for (Map.Entry<String, Object> e : h.entrySet()) {
+            String key = e.getKey();
+            String val = (String)e.getValue();
+            if (val.length() > 40) {
+                val = val.substring(0, 37) + "...";
+            }
+            out.println(key + "=" + val);
+        }
+    }
+
+    /**
+     * Prints this property list out to the specified output stream.
+     * This method is useful for debugging.
+     *
+     * @param   out   an output stream.
+     * @throws  ClassCastException if any key in this property list
+     *          is not a string.
+     * @since   1.1
+     */
+    /*
+     * Rather than use an anonymous inner class to share common code, this
+     * method is duplicated in order to ensure that a non-1.1 compiler can
+     * compile this file.
+     */
+    public void list(PrintWriter out) {
+        out.println("-- listing properties --");
+        Map<String, Object> h = new HashMap<>();
+        enumerate(h);
+        for (Map.Entry<String, Object> e : h.entrySet()) {
+            String key = e.getKey();
+            String val = (String)e.getValue();
+            if (val.length() > 40) {
+                val = val.substring(0, 37) + "...";
+            }
+            out.println(key + "=" + val);
+        }
+    }
+
+    /**
+     * Enumerates all key/value pairs into the specified Map.
+     * @param h the Map
+     * @throws ClassCastException if any of the property keys
+     *         is not of String type.
+     */
+    private void enumerate(Map<String, Object> h) {
+        if (defaults != null) {
+            defaults.enumerate(h);
+        }
+        for (Map.Entry<Object, Object> e : entrySet()) {
+            String key = (String)e.getKey();
+            h.put(key, e.getValue());
+        }
+    }
+
+    /**
+     * Enumerates all key/value pairs into the specified Map
+     * and omits the property if the key or value is not a string.
+     * @param h the Map
+     */
+    private void enumerateStringProperties(Map<String, String> h) {
+        if (defaults != null) {
+            defaults.enumerateStringProperties(h);
+        }
+        for (Map.Entry<Object, Object> e : entrySet()) {
+            Object k = e.getKey();
+            Object v = e.getValue();
+            if (k instanceof String && v instanceof String) {
+                h.put((String) k, (String) v);
+            }
+        }
+    }
+
+    /**
+     * Convert a nibble to a hex character
+     * @param   nibble  the nibble to convert.
+     */
+    private static char toHex(int nibble) {
+        return hexDigit[(nibble & 0xF)];
+    }
+
+    /** A table of hex digits */
+    private static final char[] hexDigit = {
+        '0','1','2','3','4','5','6','7','8','9','A','B','C','D','E','F'
+    };
+
+    //
+    // Hashtable methods overridden and delegated to a ConcurrentHashMap instance
+
+    @Override
+    public int size() {
+        return map.size();
+    }
+
+    @Override
+    public boolean isEmpty() {
+        return map.isEmpty();
+    }
+
+    @Override
+    public Enumeration<Object> keys() {
+        // CHM.keys() returns Iterator w/ remove() - instead wrap keySet()
+        return Collections.enumeration(map.keySet());
+    }
+
+    @Override
+    public Enumeration<Object> elements() {
+        // CHM.elements() returns Iterator w/ remove() - instead wrap values()
+        return Collections.enumeration(map.values());
+    }
+
+    @Override
+    public boolean contains(Object value) {
+        return map.contains(value);
+    }
+
+    @Override
+    public boolean containsValue(Object value) {
+        return map.containsValue(value);
+    }
+
+    @Override
+    public boolean containsKey(Object key) {
+        return map.containsKey(key);
+    }
+
+    @Override
+    public Object get(Object key) {
+        return map.get(key);
+    }
+
+    @Override
+    public synchronized Object put(Object key, Object value) {
+        return map.put(key, value);
+    }
+
+    @Override
+    public synchronized Object remove(Object key) {
+        return map.remove(key);
+    }
+
+    @Override
+    public synchronized void putAll(Map<?, ?> t) {
+        map.putAll(t);
+    }
+
+    @Override
+    public synchronized void clear() {
+        map.clear();
+    }
+
+    @Override
+    public synchronized String toString() {
+        return map.toString();
+    }
+
+    @Override
+    public Set<Object> keySet() {
+        return Collections.synchronizedSet(map.keySet(), this);
+    }
+
+    @Override
+    public Collection<Object> values() {
+        return Collections.synchronizedCollection(map.values(), this);
+    }
+
+    @Override
+    public Set<Map.Entry<Object, Object>> entrySet() {
+        return Collections.synchronizedSet(new EntrySet(map.entrySet()), this);
+    }
+
+    /*
+     * Properties.entrySet() should not support add/addAll, however
+     * ConcurrentHashMap.entrySet() provides add/addAll.  This class wraps the
+     * Set returned from CHM, changing add/addAll to throw UOE.
+     */
+    private static class EntrySet implements Set<Map.Entry<Object, Object>> {
+        private Set<Map.Entry<Object,Object>> entrySet;
+
+        private EntrySet(Set<Map.Entry<Object, Object>> entrySet) {
+            this.entrySet = entrySet;
+        }
+
+        @Override public int size() { return entrySet.size(); }
+        @Override public boolean isEmpty() { return entrySet.isEmpty(); }
+        @Override public boolean contains(Object o) { return entrySet.contains(o); }
+        @Override public Object[] toArray() { return entrySet.toArray(); }
+        @Override public <T> T[] toArray(T[] a) { return entrySet.toArray(a); }
+        @Override public void clear() { entrySet.clear(); }
+        @Override public boolean remove(Object o) { return entrySet.remove(o); }
+
+        @Override
+        public boolean add(Map.Entry<Object, Object> e) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public boolean addAll(Collection<? extends Map.Entry<Object, Object>> c) {
+            throw new UnsupportedOperationException();
+        }
+
+        @Override
+        public boolean containsAll(Collection<?> c) {
+            return entrySet.containsAll(c);
+        }
+
+        @Override
+        public boolean removeAll(Collection<?> c) {
+            return entrySet.removeAll(c);
+        }
+
+        @Override
+        public boolean retainAll(Collection<?> c) {
+            return entrySet.retainAll(c);
+        }
+
+        @Override
+        public Iterator<Map.Entry<Object, Object>> iterator() {
+            return entrySet.iterator();
+        }
+    }
+
+    @Override
+    public synchronized boolean equals(Object o) {
+        return map.equals(o);
+    }
+
+    @Override
+    public synchronized int hashCode() {
+        return map.hashCode();
+    }
+
+    @Override
+    public Object getOrDefault(Object key, Object defaultValue) {
+        return map.getOrDefault(key, defaultValue);
+    }
+
+    @Override
+    public synchronized void forEach(BiConsumer<? super Object, ? super Object> action) {
+        map.forEach(action);
+    }
+
+    @Override
+    public synchronized void replaceAll(BiFunction<? super Object, ? super Object, ?> function) {
+        map.replaceAll(function);
+    }
+
+    @Override
+    public synchronized Object putIfAbsent(Object key, Object value) {
+        return map.putIfAbsent(key, value);
+    }
+
+    @Override
+    public synchronized boolean remove(Object key, Object value) {
+        return map.remove(key, value);
+    }
+
+    @Override
+    public synchronized boolean replace(Object key, Object oldValue, Object newValue) {
+        return map.replace(key, oldValue, newValue);
+    }
+
+    @Override
+    public synchronized Object replace(Object key, Object value) {
+        return map.replace(key, value);
+    }
+
+    @Override
+    public synchronized Object computeIfAbsent(Object key,
+            Function<? super Object, ?> mappingFunction) {
+        return map.computeIfAbsent(key, mappingFunction);
+    }
+
+    @Override
+    public synchronized Object computeIfPresent(Object key,
+            BiFunction<? super Object, ? super Object, ?> remappingFunction) {
+        return map.computeIfPresent(key, remappingFunction);
+    }
+
+    @Override
+    public synchronized Object compute(Object key,
+            BiFunction<? super Object, ? super Object, ?> remappingFunction) {
+        return map.compute(key, remappingFunction);
+    }
+
+    @Override
+    public synchronized Object merge(Object key, Object value,
+            BiFunction<? super Object, ? super Object, ?> remappingFunction) {
+        return map.merge(key, value, remappingFunction);
+    }
+
+    //
+    // Special Hashtable methods
+
+    @Override
+    protected void rehash() { /* no-op */ }
+
+    @Override
+    public synchronized Object clone() {
+        Properties clone = (Properties) cloneHashtable();
+        clone.map = new ConcurrentHashMap<>(map);
+        return clone;
+    }
+
+    //
+    // Hashtable serialization overrides
+    // (these should emit and consume Hashtable-compatible stream)
+
+    @Override
+    void writeHashtable(ObjectOutputStream s) throws IOException {
+        List<Object> entryStack = new ArrayList<>(map.size() * 2); // an estimate
+
+        for (Map.Entry<Object, Object> entry : map.entrySet()) {
+            entryStack.add(entry.getValue());
+            entryStack.add(entry.getKey());
+        }
+
+        // Write out the simulated threshold, loadfactor
+        float loadFactor = 0.75f;
+        int count = entryStack.size() / 2;
+        int length = (int)(count / loadFactor) + (count / 20) + 3;
+        if (length > count && (length & 1) == 0) {
+            length--;
+        }
+        synchronized (map) { // in case of multiple concurrent serializations
+            defaultWriteHashtable(s, length, loadFactor);
+        }
+
+        // Write out simulated length and real count of elements
+        s.writeInt(length);
+        s.writeInt(count);
+
+        // Write out the key/value objects from the stacked entries
+        for (int i = entryStack.size() - 1; i >= 0; i--) {
+            s.writeObject(entryStack.get(i));
+        }
+    }
+
+    @Override
+    void readHashtable(ObjectInputStream s) throws IOException,
+            ClassNotFoundException {
+        // Read in the threshold and loadfactor
+        s.defaultReadObject();
+
+        // Read the original length of the array and number of elements
+        int origlength = s.readInt();
+        int elements = s.readInt();
+
+        // Validate # of elements
+        if (elements < 0) {
+            throw new StreamCorruptedException("Illegal # of Elements: " + elements);
+        }
+
+        // create CHM of appropriate capacity
+        map = new ConcurrentHashMap<>(elements);
+
+        // Read all the key/value objects
+        for (; elements > 0; elements--) {
+            Object key = s.readObject();
+            Object value = s.readObject();
+            map.put(key, value);
+        }
+    }
+}