src/java.base/share/classes/java/io/DataInputStream.java
changeset 58242 94bb65cb37d3
parent 47216 71c04702a3d5
child 58288 48e480e56aad
equal deleted inserted replaced
58241:33de7752835c 58242:94bb65cb37d3
     1 /*
     1 /*
     2  * Copyright (c) 1994, 2016, Oracle and/or its affiliates. All rights reserved.
     2  * Copyright (c) 1994, 2019, Oracle and/or its affiliates. All rights reserved.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
     4  *
     4  *
     5  * This code is free software; you can redistribute it and/or modify it
     5  * This code is free software; you can redistribute it and/or modify it
     6  * under the terms of the GNU General Public License version 2 only, as
     6  * under the terms of the GNU General Public License version 2 only, as
     7  * published by the Free Software Foundation.  Oracle designates this
     7  * published by the Free Software Foundation.  Oracle designates this
    87      *
    87      *
    88      * @param      b   the buffer into which the data is read.
    88      * @param      b   the buffer into which the data is read.
    89      * @return     the total number of bytes read into the buffer, or
    89      * @return     the total number of bytes read into the buffer, or
    90      *             <code>-1</code> if there is no more data because the end
    90      *             <code>-1</code> if there is no more data because the end
    91      *             of the stream has been reached.
    91      *             of the stream has been reached.
    92      * @exception  IOException if the first byte cannot be read for any reason
    92      * @throws     IOException if the first byte cannot be read for any reason
    93      * other than end of file, the stream has been closed and the underlying
    93      *             other than end of file, the stream has been closed and the underlying
    94      * input stream does not support reading after close, or another I/O
    94      *             input stream does not support reading after close, or another I/O
    95      * error occurs.
    95      *             error occurs.
    96      * @see        java.io.FilterInputStream#in
    96      * @see        java.io.FilterInputStream#in
    97      * @see        java.io.InputStream#read(byte[], int, int)
    97      * @see        java.io.InputStream#read(byte[], int, int)
    98      */
    98      */
    99     public final int read(byte b[]) throws IOException {
    99     public final int read(byte b[]) throws IOException {
   100         return in.read(b, 0, b.length);
   100         return in.read(b, 0, b.length);
   127      * <p> In every case, elements <code>b[0]</code> through
   127      * <p> In every case, elements <code>b[0]</code> through
   128      * <code>b[off]</code> and elements <code>b[off+len]</code> through
   128      * <code>b[off]</code> and elements <code>b[off+len]</code> through
   129      * <code>b[b.length-1]</code> are unaffected.
   129      * <code>b[b.length-1]</code> are unaffected.
   130      *
   130      *
   131      * @param      b     the buffer into which the data is read.
   131      * @param      b     the buffer into which the data is read.
   132      * @param off the start offset in the destination array <code>b</code>
   132      * @param      off the start offset in the destination array <code>b</code>
   133      * @param      len   the maximum number of bytes read.
   133      * @param      len   the maximum number of bytes read.
   134      * @return     the total number of bytes read into the buffer, or
   134      * @return     the total number of bytes read into the buffer, or
   135      *             <code>-1</code> if there is no more data because the end
   135      *             <code>-1</code> if there is no more data because the end
   136      *             of the stream has been reached.
   136      *             of the stream has been reached.
   137      * @exception  NullPointerException If <code>b</code> is <code>null</code>.
   137      * @throws     NullPointerException If <code>b</code> is <code>null</code>.
   138      * @exception  IndexOutOfBoundsException If <code>off</code> is negative,
   138      * @throws     IndexOutOfBoundsException If <code>off</code> is negative,
   139      * <code>len</code> is negative, or <code>len</code> is greater than
   139      *             <code>len</code> is negative, or <code>len</code> is greater than
   140      * <code>b.length - off</code>
   140      *             <code>b.length - off</code>
   141      * @exception  IOException if the first byte cannot be read for any reason
   141      * @throws     IOException if the first byte cannot be read for any reason
   142      * other than end of file, the stream has been closed and the underlying
   142      *             other than end of file, the stream has been closed and the underlying
   143      * input stream does not support reading after close, or another I/O
   143      *             input stream does not support reading after close, or another I/O
   144      * error occurs.
   144      *             error occurs.
   145      * @see        java.io.FilterInputStream#in
   145      * @see        java.io.FilterInputStream#in
   146      * @see        java.io.InputStream#read(byte[], int, int)
   146      * @see        java.io.InputStream#read(byte[], int, int)
   147      */
   147      */
   148     public final int read(byte b[], int off, int len) throws IOException {
   148     public final int read(byte b[], int off, int len) throws IOException {
   149         return in.read(b, off, len);
   149         return in.read(b, off, len);
   179      * input stream.
   179      * input stream.
   180      *
   180      *
   181      * @param      b     the buffer into which the data is read.
   181      * @param      b     the buffer into which the data is read.
   182      * @param      off   the start offset in the data array {@code b}.
   182      * @param      off   the start offset in the data array {@code b}.
   183      * @param      len   the number of bytes to read.
   183      * @param      len   the number of bytes to read.
   184      * @exception  NullPointerException if {@code b} is {@code null}.
   184      * @throws     NullPointerException if {@code b} is {@code null}.
   185      * @exception  IndexOutOfBoundsException if {@code off} is negative,
   185      * @throws     IndexOutOfBoundsException if {@code off} is negative,
   186      *             {@code len} is negative, or {@code len} is greater than
   186      *             {@code len} is negative, or {@code len} is greater than
   187      *             {@code b.length - off}.
   187      *             {@code b.length - off}.
   188      * @exception  EOFException  if this input stream reaches the end before
   188      * @throws     EOFException  if this input stream reaches the end before
   189      *             reading all the bytes.
   189      *             reading all the bytes.
   190      * @exception  IOException   the stream has been closed and the contained
   190      * @throws     IOException   the stream has been closed and the contained
   191      *             input stream does not support reading after close, or
   191      *             input stream does not support reading after close, or
   192      *             another I/O error occurs.
   192      *             another I/O error occurs.
   193      * @see        java.io.FilterInputStream#in
   193      * @see        java.io.FilterInputStream#in
   194      */
   194      */
   195     public final void readFully(byte b[], int off, int len) throws IOException {
   195     public final void readFully(byte b[], int off, int len) throws IOException {
   211      * Bytes for this operation are read from the contained
   211      * Bytes for this operation are read from the contained
   212      * input stream.
   212      * input stream.
   213      *
   213      *
   214      * @param      n   the number of bytes to be skipped.
   214      * @param      n   the number of bytes to be skipped.
   215      * @return     the actual number of bytes skipped.
   215      * @return     the actual number of bytes skipped.
   216      * @exception  IOException  if the contained input stream does not support
   216      * @throws     IOException  if the contained input stream does not support
   217      *             seek, or the stream has been closed and
   217      *             seek, or the stream has been closed and
   218      *             the contained input stream does not support
   218      *             the contained input stream does not support
   219      *             reading after close, or another I/O error occurs.
   219      *             reading after close, or another I/O error occurs.
   220      */
   220      */
   221     public final int skipBytes(int n) throws IOException {
   221     public final int skipBytes(int n) throws IOException {
   235      * <p>
   235      * <p>
   236      * Bytes for this operation are read from the contained
   236      * Bytes for this operation are read from the contained
   237      * input stream.
   237      * input stream.
   238      *
   238      *
   239      * @return     the <code>boolean</code> value read.
   239      * @return     the <code>boolean</code> value read.
   240      * @exception  EOFException  if this input stream has reached the end.
   240      * @throws     EOFException  if this input stream has reached the end.
   241      * @exception  IOException   the stream has been closed and the contained
   241      * @throws     IOException   the stream has been closed and the contained
   242      *             input stream does not support reading after close, or
   242      *             input stream does not support reading after close, or
   243      *             another I/O error occurs.
   243      *             another I/O error occurs.
   244      * @see        java.io.FilterInputStream#in
   244      * @see        java.io.FilterInputStream#in
   245      */
   245      */
   246     public final boolean readBoolean() throws IOException {
   246     public final boolean readBoolean() throws IOException {
   258      * for this operation are read from the contained
   258      * for this operation are read from the contained
   259      * input stream.
   259      * input stream.
   260      *
   260      *
   261      * @return     the next byte of this input stream as a signed 8-bit
   261      * @return     the next byte of this input stream as a signed 8-bit
   262      *             <code>byte</code>.
   262      *             <code>byte</code>.
   263      * @exception  EOFException  if this input stream has reached the end.
   263      * @throws     EOFException  if this input stream has reached the end.
   264      * @exception  IOException   the stream has been closed and the contained
   264      * @throws     IOException   the stream has been closed and the contained
   265      *             input stream does not support reading after close, or
   265      *             input stream does not support reading after close, or
   266      *             another I/O error occurs.
   266      *             another I/O error occurs.
   267      * @see        java.io.FilterInputStream#in
   267      * @see        java.io.FilterInputStream#in
   268      */
   268      */
   269     public final byte readByte() throws IOException {
   269     public final byte readByte() throws IOException {
   281      * for this operation are read from the contained
   281      * for this operation are read from the contained
   282      * input stream.
   282      * input stream.
   283      *
   283      *
   284      * @return     the next byte of this input stream, interpreted as an
   284      * @return     the next byte of this input stream, interpreted as an
   285      *             unsigned 8-bit number.
   285      *             unsigned 8-bit number.
   286      * @exception  EOFException  if this input stream has reached the end.
   286      * @throws     EOFException  if this input stream has reached the end.
   287      * @exception  IOException   the stream has been closed and the contained
   287      * @throws     IOException   the stream has been closed and the contained
   288      *             input stream does not support reading after close, or
   288      *             input stream does not support reading after close, or
   289      *             another I/O error occurs.
   289      *             another I/O error occurs.
   290      * @see         java.io.FilterInputStream#in
   290      * @see         java.io.FilterInputStream#in
   291      */
   291      */
   292     public final int readUnsignedByte() throws IOException {
   292     public final int readUnsignedByte() throws IOException {
   304      * for this operation are read from the contained
   304      * for this operation are read from the contained
   305      * input stream.
   305      * input stream.
   306      *
   306      *
   307      * @return     the next two bytes of this input stream, interpreted as a
   307      * @return     the next two bytes of this input stream, interpreted as a
   308      *             signed 16-bit number.
   308      *             signed 16-bit number.
   309      * @exception  EOFException  if this input stream reaches the end before
   309      * @throws     EOFException  if this input stream reaches the end before
   310      *               reading two bytes.
   310      *               reading two bytes.
   311      * @exception  IOException   the stream has been closed and the contained
   311      * @throws     IOException   the stream has been closed and the contained
   312      *             input stream does not support reading after close, or
   312      *             input stream does not support reading after close, or
   313      *             another I/O error occurs.
   313      *             another I/O error occurs.
   314      * @see        java.io.FilterInputStream#in
   314      * @see        java.io.FilterInputStream#in
   315      */
   315      */
   316     public final short readShort() throws IOException {
   316     public final short readShort() throws IOException {
   329      * for this operation are read from the contained
   329      * for this operation are read from the contained
   330      * input stream.
   330      * input stream.
   331      *
   331      *
   332      * @return     the next two bytes of this input stream, interpreted as an
   332      * @return     the next two bytes of this input stream, interpreted as an
   333      *             unsigned 16-bit integer.
   333      *             unsigned 16-bit integer.
   334      * @exception  EOFException  if this input stream reaches the end before
   334      * @throws     EOFException  if this input stream reaches the end before
   335      *             reading two bytes.
   335      *             reading two bytes.
   336      * @exception  IOException   the stream has been closed and the contained
   336      * @throws     IOException   the stream has been closed and the contained
   337      *             input stream does not support reading after close, or
   337      *             input stream does not support reading after close, or
   338      *             another I/O error occurs.
   338      *             another I/O error occurs.
   339      * @see        java.io.FilterInputStream#in
   339      * @see        java.io.FilterInputStream#in
   340      */
   340      */
   341     public final int readUnsignedShort() throws IOException {
   341     public final int readUnsignedShort() throws IOException {
   354      * for this operation are read from the contained
   354      * for this operation are read from the contained
   355      * input stream.
   355      * input stream.
   356      *
   356      *
   357      * @return     the next two bytes of this input stream, interpreted as a
   357      * @return     the next two bytes of this input stream, interpreted as a
   358      *             <code>char</code>.
   358      *             <code>char</code>.
   359      * @exception  EOFException  if this input stream reaches the end before
   359      * @throws     EOFException  if this input stream reaches the end before
   360      *               reading two bytes.
   360      *               reading two bytes.
   361      * @exception  IOException   the stream has been closed and the contained
   361      * @throws     IOException   the stream has been closed and the contained
   362      *             input stream does not support reading after close, or
   362      *             input stream does not support reading after close, or
   363      *             another I/O error occurs.
   363      *             another I/O error occurs.
   364      * @see        java.io.FilterInputStream#in
   364      * @see        java.io.FilterInputStream#in
   365      */
   365      */
   366     public final char readChar() throws IOException {
   366     public final char readChar() throws IOException {
   379      * for this operation are read from the contained
   379      * for this operation are read from the contained
   380      * input stream.
   380      * input stream.
   381      *
   381      *
   382      * @return     the next four bytes of this input stream, interpreted as an
   382      * @return     the next four bytes of this input stream, interpreted as an
   383      *             <code>int</code>.
   383      *             <code>int</code>.
   384      * @exception  EOFException  if this input stream reaches the end before
   384      * @throws     EOFException  if this input stream reaches the end before
   385      *               reading four bytes.
   385      *               reading four bytes.
   386      * @exception  IOException   the stream has been closed and the contained
   386      * @throws     IOException   the stream has been closed and the contained
   387      *             input stream does not support reading after close, or
   387      *             input stream does not support reading after close, or
   388      *             another I/O error occurs.
   388      *             another I/O error occurs.
   389      * @see        java.io.FilterInputStream#in
   389      * @see        java.io.FilterInputStream#in
   390      */
   390      */
   391     public final int readInt() throws IOException {
   391     public final int readInt() throws IOException {
   408      * for this operation are read from the contained
   408      * for this operation are read from the contained
   409      * input stream.
   409      * input stream.
   410      *
   410      *
   411      * @return     the next eight bytes of this input stream, interpreted as a
   411      * @return     the next eight bytes of this input stream, interpreted as a
   412      *             <code>long</code>.
   412      *             <code>long</code>.
   413      * @exception  EOFException  if this input stream reaches the end before
   413      * @throws     EOFException  if this input stream reaches the end before
   414      *               reading eight bytes.
   414      *               reading eight bytes.
   415      * @exception  IOException   the stream has been closed and the contained
   415      * @throws     IOException   the stream has been closed and the contained
   416      *             input stream does not support reading after close, or
   416      *             input stream does not support reading after close, or
   417      *             another I/O error occurs.
   417      *             another I/O error occurs.
   418      * @see        java.io.FilterInputStream#in
   418      * @see        java.io.FilterInputStream#in
   419      */
   419      */
   420     public final long readLong() throws IOException {
   420     public final long readLong() throws IOException {
   437      * for this operation are read from the contained
   437      * for this operation are read from the contained
   438      * input stream.
   438      * input stream.
   439      *
   439      *
   440      * @return     the next four bytes of this input stream, interpreted as a
   440      * @return     the next four bytes of this input stream, interpreted as a
   441      *             <code>float</code>.
   441      *             <code>float</code>.
   442      * @exception  EOFException  if this input stream reaches the end before
   442      * @throws     EOFException  if this input stream reaches the end before
   443      *               reading four bytes.
   443      *               reading four bytes.
   444      * @exception  IOException   the stream has been closed and the contained
   444      * @throws     IOException   the stream has been closed and the contained
   445      *             input stream does not support reading after close, or
   445      *             input stream does not support reading after close, or
   446      *             another I/O error occurs.
   446      *             another I/O error occurs.
   447      * @see        java.io.DataInputStream#readInt()
   447      * @see        java.io.DataInputStream#readInt()
   448      * @see        java.lang.Float#intBitsToFloat(int)
   448      * @see        java.lang.Float#intBitsToFloat(int)
   449      */
   449      */
   459      * for this operation are read from the contained
   459      * for this operation are read from the contained
   460      * input stream.
   460      * input stream.
   461      *
   461      *
   462      * @return     the next eight bytes of this input stream, interpreted as a
   462      * @return     the next eight bytes of this input stream, interpreted as a
   463      *             <code>double</code>.
   463      *             <code>double</code>.
   464      * @exception  EOFException  if this input stream reaches the end before
   464      * @throws     EOFException  if this input stream reaches the end before
   465      *               reading eight bytes.
   465      *               reading eight bytes.
   466      * @exception  IOException   the stream has been closed and the contained
   466      * @throws     IOException   the stream has been closed and the contained
   467      *             input stream does not support reading after close, or
   467      *             input stream does not support reading after close, or
   468      *             another I/O error occurs.
   468      *             another I/O error occurs.
   469      * @see        java.io.DataInputStream#readLong()
   469      * @see        java.io.DataInputStream#readLong()
   470      * @see        java.lang.Double#longBitsToDouble(long)
   470      * @see        java.lang.Double#longBitsToDouble(long)
   471      */
   471      */
   496      *     BufferedReader d
   496      *     BufferedReader d
   497      *          =&nbsp;new&nbsp;BufferedReader(new&nbsp;InputStreamReader(in));
   497      *          =&nbsp;new&nbsp;BufferedReader(new&nbsp;InputStreamReader(in));
   498      * </pre></blockquote>
   498      * </pre></blockquote>
   499      *
   499      *
   500      * @return     the next line of text from this input stream.
   500      * @return     the next line of text from this input stream.
   501      * @exception  IOException  if an I/O error occurs.
   501      * @throws     IOException  if an I/O error occurs.
   502      * @see        java.io.BufferedReader#readLine()
   502      * @see        java.io.BufferedReader#readLine()
   503      * @see        java.io.FilterInputStream#in
   503      * @see        java.io.FilterInputStream#in
   504      */
   504      */
   505     @Deprecated
   505     @Deprecated
   506     public final String readLine() throws IOException {
   506     public final String readLine() throws IOException {
   554      * Bytes
   554      * Bytes
   555      * for this operation are read from the contained
   555      * for this operation are read from the contained
   556      * input stream.
   556      * input stream.
   557      *
   557      *
   558      * @return     a Unicode string.
   558      * @return     a Unicode string.
   559      * @exception  EOFException  if this input stream reaches the end before
   559      * @throws     EOFException  if this input stream reaches the end before
   560      *               reading all the bytes.
   560      *               reading all the bytes.
   561      * @exception  IOException   the stream has been closed and the contained
   561      * @throws     IOException   the stream has been closed and the contained
   562      *             input stream does not support reading after close, or
   562      *             input stream does not support reading after close, or
   563      *             another I/O error occurs.
   563      *             another I/O error occurs.
   564      * @exception  UTFDataFormatException if the bytes do not represent a valid
   564      * @throws     UTFDataFormatException if the bytes do not represent a valid
   565      *             modified UTF-8 encoding of a string.
   565      *             modified UTF-8 encoding of a string.
   566      * @see        java.io.DataInputStream#readUTF(java.io.DataInput)
   566      * @see        java.io.DataInputStream#readUTF(java.io.DataInput)
   567      */
   567      */
   568     public final String readUTF() throws IOException {
   568     public final String readUTF() throws IOException {
   569         return readUTF(this);
   569         return readUTF(this);
   579      * are  exactly the same as for the <code>readUTF</code>
   579      * are  exactly the same as for the <code>readUTF</code>
   580      * method of <code>DataInput</code>.
   580      * method of <code>DataInput</code>.
   581      *
   581      *
   582      * @param      in   a data input stream.
   582      * @param      in   a data input stream.
   583      * @return     a Unicode string.
   583      * @return     a Unicode string.
   584      * @exception  EOFException            if the input stream reaches the end
   584      * @throws     EOFException            if the input stream reaches the end
   585      *               before all the bytes.
   585      *               before all the bytes.
   586      * @exception  IOException   the stream has been closed and the contained
   586      * @throws     IOException   the stream has been closed and the contained
   587      *             input stream does not support reading after close, or
   587      *             input stream does not support reading after close, or
   588      *             another I/O error occurs.
   588      *             another I/O error occurs.
   589      * @exception  UTFDataFormatException  if the bytes do not represent a
   589      * @throws     UTFDataFormatException  if the bytes do not represent a
   590      *               valid modified UTF-8 encoding of a Unicode string.
   590      *               valid modified UTF-8 encoding of a Unicode string.
   591      * @see        java.io.DataInputStream#readUnsignedShort()
   591      * @see        java.io.DataInputStream#readUnsignedShort()
   592      */
   592      */
   593     public static final String readUTF(DataInput in) throws IOException {
   593     public static final String readUTF(DataInput in) throws IOException {
   594         int utflen = in.readUnsignedShort();
   594         int utflen = in.readUnsignedShort();