jdk/src/java.base/share/classes/java/lang/StringBuilder.java
changeset 25859 3317bb8137f4
parent 23010 6dadb192ad81
child 31671 362e0c0acece
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/jdk/src/java.base/share/classes/java/lang/StringBuilder.java	Sun Aug 17 15:54:13 2014 +0100
@@ -0,0 +1,439 @@
+/*
+ * Copyright (c) 2003, 2013, 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.lang;
+
+
+/**
+ * A mutable sequence of characters.  This class provides an API compatible
+ * with {@code StringBuffer}, but with no guarantee of synchronization.
+ * This class is designed for use as a drop-in replacement for
+ * {@code StringBuffer} in places where the string buffer was being
+ * used by a single thread (as is generally the case).   Where possible,
+ * it is recommended that this class be used in preference to
+ * {@code StringBuffer} as it will be faster under most implementations.
+ *
+ * <p>The principal operations on a {@code StringBuilder} are the
+ * {@code append} and {@code insert} methods, which are
+ * overloaded so as to accept data of any type. Each effectively
+ * converts a given datum to a string and then appends or inserts the
+ * characters of that string to the string builder. The
+ * {@code append} method always adds these characters at the end
+ * of the builder; the {@code insert} method adds the characters at
+ * a specified point.
+ * <p>
+ * For example, if {@code z} refers to a string builder object
+ * whose current contents are "{@code start}", then
+ * the method call {@code z.append("le")} would cause the string
+ * builder to contain "{@code startle}", whereas
+ * {@code z.insert(4, "le")} would alter the string builder to
+ * contain "{@code starlet}".
+ * <p>
+ * In general, if sb refers to an instance of a {@code StringBuilder},
+ * then {@code sb.append(x)} has the same effect as
+ * {@code sb.insert(sb.length(), x)}.
+ * <p>
+ * Every string builder has a capacity. As long as the length of the
+ * character sequence contained in the string builder does not exceed
+ * the capacity, it is not necessary to allocate a new internal
+ * buffer. If the internal buffer overflows, it is automatically made larger.
+ *
+ * <p>Instances of {@code StringBuilder} are not safe for
+ * use by multiple threads. If such synchronization is required then it is
+ * recommended that {@link java.lang.StringBuffer} be used.
+ *
+ * <p>Unless otherwise noted, passing a {@code null} argument to a constructor
+ * or method in this class will cause a {@link NullPointerException} to be
+ * thrown.
+ *
+ * @author      Michael McCloskey
+ * @see         java.lang.StringBuffer
+ * @see         java.lang.String
+ * @since       1.5
+ */
+public final class StringBuilder
+    extends AbstractStringBuilder
+    implements java.io.Serializable, CharSequence
+{
+
+    /** use serialVersionUID for interoperability */
+    static final long serialVersionUID = 4383685877147921099L;
+
+    /**
+     * Constructs a string builder with no characters in it and an
+     * initial capacity of 16 characters.
+     */
+    public StringBuilder() {
+        super(16);
+    }
+
+    /**
+     * Constructs a string builder with no characters in it and an
+     * initial capacity specified by the {@code capacity} argument.
+     *
+     * @param      capacity  the initial capacity.
+     * @throws     NegativeArraySizeException  if the {@code capacity}
+     *               argument is less than {@code 0}.
+     */
+    public StringBuilder(int capacity) {
+        super(capacity);
+    }
+
+    /**
+     * Constructs a string builder initialized to the contents of the
+     * specified string. The initial capacity of the string builder is
+     * {@code 16} plus the length of the string argument.
+     *
+     * @param   str   the initial contents of the buffer.
+     */
+    public StringBuilder(String str) {
+        super(str.length() + 16);
+        append(str);
+    }
+
+    /**
+     * Constructs a string builder that contains the same characters
+     * as the specified {@code CharSequence}. The initial capacity of
+     * the string builder is {@code 16} plus the length of the
+     * {@code CharSequence} argument.
+     *
+     * @param      seq   the sequence to copy.
+     */
+    public StringBuilder(CharSequence seq) {
+        this(seq.length() + 16);
+        append(seq);
+    }
+
+    @Override
+    public StringBuilder append(Object obj) {
+        return append(String.valueOf(obj));
+    }
+
+    @Override
+    public StringBuilder append(String str) {
+        super.append(str);
+        return this;
+    }
+
+    /**
+     * Appends the specified {@code StringBuffer} to this sequence.
+     * <p>
+     * The characters of the {@code StringBuffer} argument are appended,
+     * in order, to this sequence, increasing the
+     * length of this sequence by the length of the argument.
+     * If {@code sb} is {@code null}, then the four characters
+     * {@code "null"} are appended to this sequence.
+     * <p>
+     * Let <i>n</i> be the length of this character sequence just prior to
+     * execution of the {@code append} method. Then the character at index
+     * <i>k</i> in the new character sequence is equal to the character at
+     * index <i>k</i> in the old character sequence, if <i>k</i> is less than
+     * <i>n</i>; otherwise, it is equal to the character at index <i>k-n</i>
+     * in the argument {@code sb}.
+     *
+     * @param   sb   the {@code StringBuffer} to append.
+     * @return  a reference to this object.
+     */
+    public StringBuilder append(StringBuffer sb) {
+        super.append(sb);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(CharSequence s) {
+        super.append(s);
+        return this;
+    }
+
+    /**
+     * @throws     IndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder append(CharSequence s, int start, int end) {
+        super.append(s, start, end);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(char[] str) {
+        super.append(str);
+        return this;
+    }
+
+    /**
+     * @throws IndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder append(char[] str, int offset, int len) {
+        super.append(str, offset, len);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(boolean b) {
+        super.append(b);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(char c) {
+        super.append(c);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(int i) {
+        super.append(i);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(long lng) {
+        super.append(lng);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(float f) {
+        super.append(f);
+        return this;
+    }
+
+    @Override
+    public StringBuilder append(double d) {
+        super.append(d);
+        return this;
+    }
+
+    /**
+     * @since 1.5
+     */
+    @Override
+    public StringBuilder appendCodePoint(int codePoint) {
+        super.appendCodePoint(codePoint);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder delete(int start, int end) {
+        super.delete(start, end);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder deleteCharAt(int index) {
+        super.deleteCharAt(index);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder replace(int start, int end, String str) {
+        super.replace(start, end, str);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int index, char[] str, int offset,
+                                int len)
+    {
+        super.insert(index, str, offset, len);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, Object obj) {
+            super.insert(offset, obj);
+            return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, String str) {
+        super.insert(offset, str);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, char[] str) {
+        super.insert(offset, str);
+        return this;
+    }
+
+    /**
+     * @throws IndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int dstOffset, CharSequence s) {
+            super.insert(dstOffset, s);
+            return this;
+    }
+
+    /**
+     * @throws IndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int dstOffset, CharSequence s,
+                                int start, int end)
+    {
+        super.insert(dstOffset, s, start, end);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, boolean b) {
+        super.insert(offset, b);
+        return this;
+    }
+
+    /**
+     * @throws IndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, char c) {
+        super.insert(offset, c);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, int i) {
+        super.insert(offset, i);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, long l) {
+        super.insert(offset, l);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, float f) {
+        super.insert(offset, f);
+        return this;
+    }
+
+    /**
+     * @throws StringIndexOutOfBoundsException {@inheritDoc}
+     */
+    @Override
+    public StringBuilder insert(int offset, double d) {
+        super.insert(offset, d);
+        return this;
+    }
+
+    @Override
+    public int indexOf(String str) {
+        return super.indexOf(str);
+    }
+
+    @Override
+    public int indexOf(String str, int fromIndex) {
+        return super.indexOf(str, fromIndex);
+    }
+
+    @Override
+    public int lastIndexOf(String str) {
+        return super.lastIndexOf(str);
+    }
+
+    @Override
+    public int lastIndexOf(String str, int fromIndex) {
+        return super.lastIndexOf(str, fromIndex);
+    }
+
+    @Override
+    public StringBuilder reverse() {
+        super.reverse();
+        return this;
+    }
+
+    @Override
+    public String toString() {
+        // Create a copy, don't share the array
+        return new String(value, 0, count);
+    }
+
+    /**
+     * Save the state of the {@code StringBuilder} instance to a stream
+     * (that is, serialize it).
+     *
+     * @serialData the number of characters currently stored in the string
+     *             builder ({@code int}), followed by the characters in the
+     *             string builder ({@code char[]}).   The length of the
+     *             {@code char} array may be greater than the number of
+     *             characters currently stored in the string builder, in which
+     *             case extra characters are ignored.
+     */
+    private void writeObject(java.io.ObjectOutputStream s)
+        throws java.io.IOException {
+        s.defaultWriteObject();
+        s.writeInt(count);
+        s.writeObject(value);
+    }
+
+    /**
+     * readObject is called to restore the state of the StringBuffer from
+     * a stream.
+     */
+    private void readObject(java.io.ObjectInputStream s)
+        throws java.io.IOException, ClassNotFoundException {
+        s.defaultReadObject();
+        count = s.readInt();
+        value = (char[]) s.readObject();
+    }
+
+}