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3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
4  *
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8  * particular file as subject to the "Classpath" exception as provided
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11  * This code is distributed in the hope that it will be useful, but WITHOUT
12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
14  * version 2 for more details (a copy is included in the LICENSE file that
15  * accompanied this code).
16  *
17  * You should have received a copy of the GNU General Public License version
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24  */
25 
26 package java.io;
27 
28 /**
29  * ObjectInput extends the DataInput interface to include the reading of
30  * objects. DataInput includes methods for the input of primitive types,
31  * ObjectInput extends that interface to include objects, arrays, and Strings.
32  *
33  * @author  unascribed
34  * @see java.io.InputStream
35  * @see java.io.ObjectOutputStream
36  * @see java.io.ObjectInputStream
37  * @since   JDK1.1
38  */
39 public interface ObjectInput extends DataInput, AutoCloseable {
40     /**
41      * Read and return an object. The class that implements this interface
42      * defines where the object is "read" from.
43      *
44      * @return the object read from the stream
45      * @exception java.lang.ClassNotFoundException If the class of a serialized
46      *      object cannot be found.
47      * @exception IOException If any of the usual Input/Output
48      * related exceptions occur.
49      */
readObject()50     public Object readObject()
51         throws ClassNotFoundException, IOException;
52 
53     /**
54      * Reads a byte of data. This method will block if no input is
55      * available.
56      * @return  the byte read, or -1 if the end of the
57      *          stream is reached.
58      * @exception IOException If an I/O error has occurred.
59      */
read()60     public int read() throws IOException;
61 
62     /**
63      * Reads into an array of bytes.  This method will
64      * block until some input is available.
65      * @param b the buffer into which the data is read
66      * @return  the actual number of bytes read, -1 is
67      *          returned when the end of the stream is reached.
68      * @exception IOException If an I/O error has occurred.
69      */
read(byte b[])70     public int read(byte b[]) throws IOException;
71 
72     /**
73      * Reads into an array of bytes.  This method will
74      * block until some input is available.
75      * @param b the buffer into which the data is read
76      * @param off the start offset of the data
77      * @param len the maximum number of bytes read
78      * @return  the actual number of bytes read, -1 is
79      *          returned when the end of the stream is reached.
80      * @exception IOException If an I/O error has occurred.
81      */
read(byte b[], int off, int len)82     public int read(byte b[], int off, int len) throws IOException;
83 
84     /**
85      * Skips n bytes of input.
86      * @param n the number of bytes to be skipped
87      * @return  the actual number of bytes skipped.
88      * @exception IOException If an I/O error has occurred.
89      */
skip(long n)90     public long skip(long n) throws IOException;
91 
92     /**
93      * Returns the number of bytes that can be read
94      * without blocking.
95      * @return the number of available bytes.
96      * @exception IOException If an I/O error has occurred.
97      */
available()98     public int available() throws IOException;
99 
100     /**
101      * Closes the input stream. Must be called
102      * to release any resources associated with
103      * the stream.
104      * @exception IOException If an I/O error has occurred.
105      */
close()106     public void close() throws IOException;
107 }
108