--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/src/java.base/share/classes/java/io/DataInputStream.java Tue Sep 12 19:03:39 2017 +0200
@@ -0,0 +1,668 @@
+/*
+ * Copyright (c) 1994, 2016, 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.io;
+
+/**
+ * A data input stream lets an application read primitive Java data
+ * types from an underlying input stream in a machine-independent
+ * way. An application uses a data output stream to write data that
+ * can later be read by a data input stream.
+ * <p>
+ * DataInputStream is not necessarily safe for multithreaded access.
+ * Thread safety is optional and is the responsibility of users of
+ * methods in this class.
+ *
+ * @author Arthur van Hoff
+ * @see java.io.DataOutputStream
+ * @since 1.0
+ */
+public
+class DataInputStream extends FilterInputStream implements DataInput {
+
+ /**
+ * Creates a DataInputStream that uses the specified
+ * underlying InputStream.
+ *
+ * @param in the specified input stream
+ */
+ public DataInputStream(InputStream in) {
+ super(in);
+ }
+
+ /**
+ * working arrays initialized on demand by readUTF
+ */
+ private byte bytearr[] = new byte[80];
+ private char chararr[] = new char[80];
+
+ /**
+ * Reads some number of bytes from the contained input stream and
+ * stores them into the buffer array <code>b</code>. The number of
+ * bytes actually read is returned as an integer. This method blocks
+ * until input data is available, end of file is detected, or an
+ * exception is thrown.
+ *
+ * <p>If <code>b</code> is null, a <code>NullPointerException</code> is
+ * thrown. If the length of <code>b</code> is zero, then no bytes are
+ * read and <code>0</code> is returned; otherwise, there is an attempt
+ * to read at least one byte. If no byte is available because the
+ * stream is at end of file, the value <code>-1</code> is returned;
+ * otherwise, at least one byte is read and stored into <code>b</code>.
+ *
+ * <p>The first byte read is stored into element <code>b[0]</code>, the
+ * next one into <code>b[1]</code>, and so on. The number of bytes read
+ * is, at most, equal to the length of <code>b</code>. Let <code>k</code>
+ * be the number of bytes actually read; these bytes will be stored in
+ * elements <code>b[0]</code> through <code>b[k-1]</code>, leaving
+ * elements <code>b[k]</code> through <code>b[b.length-1]</code>
+ * unaffected.
+ *
+ * <p>The <code>read(b)</code> method has the same effect as:
+ * <blockquote><pre>
+ * read(b, 0, b.length)
+ * </pre></blockquote>
+ *
+ * @param b the buffer into which the data is read.
+ * @return the total number of bytes read into the buffer, or
+ * <code>-1</code> if there is no more data because the end
+ * of the stream has been reached.
+ * @exception IOException if the first byte cannot be read for any reason
+ * other than end of file, the stream has been closed and the underlying
+ * input stream does not support reading after close, or another I/O
+ * error occurs.
+ * @see java.io.FilterInputStream#in
+ * @see java.io.InputStream#read(byte[], int, int)
+ */
+ public final int read(byte b[]) throws IOException {
+ return in.read(b, 0, b.length);
+ }
+
+ /**
+ * Reads up to <code>len</code> bytes of data from the contained
+ * input stream into an array of bytes. An attempt is made to read
+ * as many as <code>len</code> bytes, but a smaller number may be read,
+ * possibly zero. The number of bytes actually read is returned as an
+ * integer.
+ *
+ * <p> This method blocks until input data is available, end of file is
+ * detected, or an exception is thrown.
+ *
+ * <p> If <code>len</code> is zero, then no bytes are read and
+ * <code>0</code> is returned; otherwise, there is an attempt to read at
+ * least one byte. If no byte is available because the stream is at end of
+ * file, the value <code>-1</code> is returned; otherwise, at least one
+ * byte is read and stored into <code>b</code>.
+ *
+ * <p> The first byte read is stored into element <code>b[off]</code>, the
+ * next one into <code>b[off+1]</code>, and so on. The number of bytes read
+ * is, at most, equal to <code>len</code>. Let <i>k</i> be the number of
+ * bytes actually read; these bytes will be stored in elements
+ * <code>b[off]</code> through <code>b[off+</code><i>k</i><code>-1]</code>,
+ * leaving elements <code>b[off+</code><i>k</i><code>]</code> through
+ * <code>b[off+len-1]</code> unaffected.
+ *
+ * <p> In every case, elements <code>b[0]</code> through
+ * <code>b[off]</code> and elements <code>b[off+len]</code> through
+ * <code>b[b.length-1]</code> are unaffected.
+ *
+ * @param b the buffer into which the data is read.
+ * @param off the start offset in the destination array <code>b</code>
+ * @param len the maximum number of bytes read.
+ * @return the total number of bytes read into the buffer, or
+ * <code>-1</code> if there is no more data because the end
+ * of the stream has been reached.
+ * @exception NullPointerException If <code>b</code> is <code>null</code>.
+ * @exception IndexOutOfBoundsException If <code>off</code> is negative,
+ * <code>len</code> is negative, or <code>len</code> is greater than
+ * <code>b.length - off</code>
+ * @exception IOException if the first byte cannot be read for any reason
+ * other than end of file, the stream has been closed and the underlying
+ * input stream does not support reading after close, or another I/O
+ * error occurs.
+ * @see java.io.FilterInputStream#in
+ * @see java.io.InputStream#read(byte[], int, int)
+ */
+ public final int read(byte b[], int off, int len) throws IOException {
+ return in.read(b, off, len);
+ }
+
+ /**
+ * See the general contract of the {@code readFully}
+ * method of {@code DataInput}.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @param b the buffer into which the data is read.
+ * @throws NullPointerException if {@code b} is {@code null}.
+ * @throws EOFException if this input stream reaches the end before
+ * reading all the bytes.
+ * @throws IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final void readFully(byte b[]) throws IOException {
+ readFully(b, 0, b.length);
+ }
+
+ /**
+ * See the general contract of the {@code readFully}
+ * method of {@code DataInput}.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @param b the buffer into which the data is read.
+ * @param off the start offset in the data array {@code b}.
+ * @param len the number of bytes to read.
+ * @exception NullPointerException if {@code b} is {@code null}.
+ * @exception IndexOutOfBoundsException if {@code off} is negative,
+ * {@code len} is negative, or {@code len} is greater than
+ * {@code b.length - off}.
+ * @exception EOFException if this input stream reaches the end before
+ * reading all the bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final void readFully(byte b[], int off, int len) throws IOException {
+ if (len < 0)
+ throw new IndexOutOfBoundsException();
+ int n = 0;
+ while (n < len) {
+ int count = in.read(b, off + n, len - n);
+ if (count < 0)
+ throw new EOFException();
+ n += count;
+ }
+ }
+
+ /**
+ * See the general contract of the <code>skipBytes</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes for this operation are read from the contained
+ * input stream.
+ *
+ * @param n the number of bytes to be skipped.
+ * @return the actual number of bytes skipped.
+ * @exception IOException if the contained input stream does not support
+ * seek, or the stream has been closed and
+ * the contained input stream does not support
+ * reading after close, or another I/O error occurs.
+ */
+ public final int skipBytes(int n) throws IOException {
+ int total = 0;
+ int cur = 0;
+
+ while ((total<n) && ((cur = (int) in.skip(n-total)) > 0)) {
+ total += cur;
+ }
+
+ return total;
+ }
+
+ /**
+ * See the general contract of the <code>readBoolean</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes for this operation are read from the contained
+ * input stream.
+ *
+ * @return the <code>boolean</code> value read.
+ * @exception EOFException if this input stream has reached the end.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final boolean readBoolean() throws IOException {
+ int ch = in.read();
+ if (ch < 0)
+ throw new EOFException();
+ return (ch != 0);
+ }
+
+ /**
+ * See the general contract of the <code>readByte</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next byte of this input stream as a signed 8-bit
+ * <code>byte</code>.
+ * @exception EOFException if this input stream has reached the end.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final byte readByte() throws IOException {
+ int ch = in.read();
+ if (ch < 0)
+ throw new EOFException();
+ return (byte)(ch);
+ }
+
+ /**
+ * See the general contract of the <code>readUnsignedByte</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next byte of this input stream, interpreted as an
+ * unsigned 8-bit number.
+ * @exception EOFException if this input stream has reached the end.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final int readUnsignedByte() throws IOException {
+ int ch = in.read();
+ if (ch < 0)
+ throw new EOFException();
+ return ch;
+ }
+
+ /**
+ * See the general contract of the <code>readShort</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next two bytes of this input stream, interpreted as a
+ * signed 16-bit number.
+ * @exception EOFException if this input stream reaches the end before
+ * reading two bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final short readShort() throws IOException {
+ int ch1 = in.read();
+ int ch2 = in.read();
+ if ((ch1 | ch2) < 0)
+ throw new EOFException();
+ return (short)((ch1 << 8) + (ch2 << 0));
+ }
+
+ /**
+ * See the general contract of the <code>readUnsignedShort</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next two bytes of this input stream, interpreted as an
+ * unsigned 16-bit integer.
+ * @exception EOFException if this input stream reaches the end before
+ * reading two bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final int readUnsignedShort() throws IOException {
+ int ch1 = in.read();
+ int ch2 = in.read();
+ if ((ch1 | ch2) < 0)
+ throw new EOFException();
+ return (ch1 << 8) + (ch2 << 0);
+ }
+
+ /**
+ * See the general contract of the <code>readChar</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next two bytes of this input stream, interpreted as a
+ * <code>char</code>.
+ * @exception EOFException if this input stream reaches the end before
+ * reading two bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final char readChar() throws IOException {
+ int ch1 = in.read();
+ int ch2 = in.read();
+ if ((ch1 | ch2) < 0)
+ throw new EOFException();
+ return (char)((ch1 << 8) + (ch2 << 0));
+ }
+
+ /**
+ * See the general contract of the <code>readInt</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next four bytes of this input stream, interpreted as an
+ * <code>int</code>.
+ * @exception EOFException if this input stream reaches the end before
+ * reading four bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final int readInt() throws IOException {
+ int ch1 = in.read();
+ int ch2 = in.read();
+ int ch3 = in.read();
+ int ch4 = in.read();
+ if ((ch1 | ch2 | ch3 | ch4) < 0)
+ throw new EOFException();
+ return ((ch1 << 24) + (ch2 << 16) + (ch3 << 8) + (ch4 << 0));
+ }
+
+ private byte readBuffer[] = new byte[8];
+
+ /**
+ * See the general contract of the <code>readLong</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next eight bytes of this input stream, interpreted as a
+ * <code>long</code>.
+ * @exception EOFException if this input stream reaches the end before
+ * reading eight bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.FilterInputStream#in
+ */
+ public final long readLong() throws IOException {
+ readFully(readBuffer, 0, 8);
+ return (((long)readBuffer[0] << 56) +
+ ((long)(readBuffer[1] & 255) << 48) +
+ ((long)(readBuffer[2] & 255) << 40) +
+ ((long)(readBuffer[3] & 255) << 32) +
+ ((long)(readBuffer[4] & 255) << 24) +
+ ((readBuffer[5] & 255) << 16) +
+ ((readBuffer[6] & 255) << 8) +
+ ((readBuffer[7] & 255) << 0));
+ }
+
+ /**
+ * See the general contract of the <code>readFloat</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next four bytes of this input stream, interpreted as a
+ * <code>float</code>.
+ * @exception EOFException if this input stream reaches the end before
+ * reading four bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.DataInputStream#readInt()
+ * @see java.lang.Float#intBitsToFloat(int)
+ */
+ public final float readFloat() throws IOException {
+ return Float.intBitsToFloat(readInt());
+ }
+
+ /**
+ * See the general contract of the <code>readDouble</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return the next eight bytes of this input stream, interpreted as a
+ * <code>double</code>.
+ * @exception EOFException if this input stream reaches the end before
+ * reading eight bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @see java.io.DataInputStream#readLong()
+ * @see java.lang.Double#longBitsToDouble(long)
+ */
+ public final double readDouble() throws IOException {
+ return Double.longBitsToDouble(readLong());
+ }
+
+ private char lineBuffer[];
+
+ /**
+ * See the general contract of the <code>readLine</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @deprecated This method does not properly convert bytes to characters.
+ * As of JDK 1.1, the preferred way to read lines of text is via the
+ * <code>BufferedReader.readLine()</code> method. Programs that use the
+ * <code>DataInputStream</code> class to read lines can be converted to use
+ * the <code>BufferedReader</code> class by replacing code of the form:
+ * <blockquote><pre>
+ * DataInputStream d = new DataInputStream(in);
+ * </pre></blockquote>
+ * with:
+ * <blockquote><pre>
+ * BufferedReader d
+ * = new BufferedReader(new InputStreamReader(in));
+ * </pre></blockquote>
+ *
+ * @return the next line of text from this input stream.
+ * @exception IOException if an I/O error occurs.
+ * @see java.io.BufferedReader#readLine()
+ * @see java.io.FilterInputStream#in
+ */
+ @Deprecated
+ public final String readLine() throws IOException {
+ char buf[] = lineBuffer;
+
+ if (buf == null) {
+ buf = lineBuffer = new char[128];
+ }
+
+ int room = buf.length;
+ int offset = 0;
+ int c;
+
+loop: while (true) {
+ switch (c = in.read()) {
+ case -1:
+ case '\n':
+ break loop;
+
+ case '\r':
+ int c2 = in.read();
+ if ((c2 != '\n') && (c2 != -1)) {
+ if (!(in instanceof PushbackInputStream)) {
+ this.in = new PushbackInputStream(in);
+ }
+ ((PushbackInputStream)in).unread(c2);
+ }
+ break loop;
+
+ default:
+ if (--room < 0) {
+ buf = new char[offset + 128];
+ room = buf.length - offset - 1;
+ System.arraycopy(lineBuffer, 0, buf, 0, offset);
+ lineBuffer = buf;
+ }
+ buf[offset++] = (char) c;
+ break;
+ }
+ }
+ if ((c == -1) && (offset == 0)) {
+ return null;
+ }
+ return String.copyValueOf(buf, 0, offset);
+ }
+
+ /**
+ * See the general contract of the <code>readUTF</code>
+ * method of <code>DataInput</code>.
+ * <p>
+ * Bytes
+ * for this operation are read from the contained
+ * input stream.
+ *
+ * @return a Unicode string.
+ * @exception EOFException if this input stream reaches the end before
+ * reading all the bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @exception UTFDataFormatException if the bytes do not represent a valid
+ * modified UTF-8 encoding of a string.
+ * @see java.io.DataInputStream#readUTF(java.io.DataInput)
+ */
+ public final String readUTF() throws IOException {
+ return readUTF(this);
+ }
+
+ /**
+ * Reads from the
+ * stream <code>in</code> a representation
+ * of a Unicode character string encoded in
+ * <a href="DataInput.html#modified-utf-8">modified UTF-8</a> format;
+ * this string of characters is then returned as a <code>String</code>.
+ * The details of the modified UTF-8 representation
+ * are exactly the same as for the <code>readUTF</code>
+ * method of <code>DataInput</code>.
+ *
+ * @param in a data input stream.
+ * @return a Unicode string.
+ * @exception EOFException if the input stream reaches the end
+ * before all the bytes.
+ * @exception IOException the stream has been closed and the contained
+ * input stream does not support reading after close, or
+ * another I/O error occurs.
+ * @exception UTFDataFormatException if the bytes do not represent a
+ * valid modified UTF-8 encoding of a Unicode string.
+ * @see java.io.DataInputStream#readUnsignedShort()
+ */
+ public static final String readUTF(DataInput in) throws IOException {
+ int utflen = in.readUnsignedShort();
+ byte[] bytearr = null;
+ char[] chararr = null;
+ if (in instanceof DataInputStream) {
+ DataInputStream dis = (DataInputStream)in;
+ if (dis.bytearr.length < utflen){
+ dis.bytearr = new byte[utflen*2];
+ dis.chararr = new char[utflen*2];
+ }
+ chararr = dis.chararr;
+ bytearr = dis.bytearr;
+ } else {
+ bytearr = new byte[utflen];
+ chararr = new char[utflen];
+ }
+
+ int c, char2, char3;
+ int count = 0;
+ int chararr_count=0;
+
+ in.readFully(bytearr, 0, utflen);
+
+ while (count < utflen) {
+ c = (int) bytearr[count] & 0xff;
+ if (c > 127) break;
+ count++;
+ chararr[chararr_count++]=(char)c;
+ }
+
+ while (count < utflen) {
+ c = (int) bytearr[count] & 0xff;
+ switch (c >> 4) {
+ case 0: case 1: case 2: case 3: case 4: case 5: case 6: case 7:
+ /* 0xxxxxxx*/
+ count++;
+ chararr[chararr_count++]=(char)c;
+ break;
+ case 12: case 13:
+ /* 110x xxxx 10xx xxxx*/
+ count += 2;
+ if (count > utflen)
+ throw new UTFDataFormatException(
+ "malformed input: partial character at end");
+ char2 = (int) bytearr[count-1];
+ if ((char2 & 0xC0) != 0x80)
+ throw new UTFDataFormatException(
+ "malformed input around byte " + count);
+ chararr[chararr_count++]=(char)(((c & 0x1F) << 6) |
+ (char2 & 0x3F));
+ break;
+ case 14:
+ /* 1110 xxxx 10xx xxxx 10xx xxxx */
+ count += 3;
+ if (count > utflen)
+ throw new UTFDataFormatException(
+ "malformed input: partial character at end");
+ char2 = (int) bytearr[count-2];
+ char3 = (int) bytearr[count-1];
+ if (((char2 & 0xC0) != 0x80) || ((char3 & 0xC0) != 0x80))
+ throw new UTFDataFormatException(
+ "malformed input around byte " + (count-1));
+ chararr[chararr_count++]=(char)(((c & 0x0F) << 12) |
+ ((char2 & 0x3F) << 6) |
+ ((char3 & 0x3F) << 0));
+ break;
+ default:
+ /* 10xx xxxx, 1111 xxxx */
+ throw new UTFDataFormatException(
+ "malformed input around byte " + count);
+ }
+ }
+ // The number of chars produced may be less than utflen
+ return new String(chararr, 0, chararr_count);
+ }
+}