1 /*
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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
9  * by Oracle in the LICENSE file that accompanied this code.
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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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19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
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24  */
25 
26 package java.lang;
27 
28 import java.io.IOException;
29 
30 /**
31  * A <tt>Readable</tt> is a source of characters. Characters from
32  * a <tt>Readable</tt> are made available to callers of the read
33  * method via a {@link java.nio.CharBuffer CharBuffer}.
34  *
35  * @since 1.5
36  */
37 public interface Readable {
38 
39     /**
40      * Attempts to read characters into the specified character buffer.
41      * The buffer is used as a repository of characters as-is: the only
42      * changes made are the results of a put operation. No flipping or
43      * rewinding of the buffer is performed.
44      *
45      * @param cb the buffer to read characters into
46      * @return The number of {@code char} values added to the buffer,
47      *                 or -1 if this source of characters is at its end
48      * @throws IOException if an I/O error occurs
49      * @throws NullPointerException if cb is null
50      * @throws java.nio.ReadOnlyBufferException if cb is a read only buffer
51      */
read(java.nio.CharBuffer cb)52     public int read(java.nio.CharBuffer cb) throws IOException;
53 }
54