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Diffstat (limited to 'libjava/java/io/StringReader.java')
-rw-r--r-- | libjava/java/io/StringReader.java | 139 |
1 files changed, 139 insertions, 0 deletions
diff --git a/libjava/java/io/StringReader.java b/libjava/java/io/StringReader.java new file mode 100644 index 00000000000..08e8d0c4f15 --- /dev/null +++ b/libjava/java/io/StringReader.java @@ -0,0 +1,139 @@ +/* Copyright (C) 1998, 1999 Cygnus Solutions + + This file is part of libgcj. + +This software is copyrighted work licensed under the terms of the +Libgcj License. Please consult the file "LIBGCJ_LICENSE" for +details. */ + +package java.io; + +/** + * @author Warren Levy <warrenl@cygnus.com> + * @date October 19, 1998. + */ +/* Written using "Java Class Libraries", 2nd edition, ISBN 0-201-31002-3 + * "The Java Language Specification", ISBN 0-201-63451-1 + * plus online API docs for JDK 1.2 beta from http://www.javasoft.com. + * Status: Believed complete and correct + */ + +public class StringReader extends Reader +{ + /* A String provided by the creator of the stream. */ + private String buf; + + /* Position of the next char in buf to be read. */ + private int pos; + + /* The currently marked position in the stream. */ + private int markedPos; + + /* The index in buf one greater than the last valid character. */ + private int count; + + public StringReader(String buffer) + { + super(); + buf = buffer; + + count = buffer.length(); + markedPos = pos = 0; + } + + public void close() + { + synchronized (lock) + { + buf = null; + } + } + + public void mark(int readAheadLimit) throws IOException + { + synchronized (lock) + { + if (buf == null) + throw new IOException(); + + // readAheadLimit is ignored per Java Class Lib. book, p. 1692. + markedPos = pos; + } + } + + public boolean markSupported() + { + return true; + } + + public int read() throws IOException + { + synchronized (lock) + { + if (buf == null) + throw new IOException(); + + if (pos < count) + return ((int) buf.charAt(pos++)) & 0xFFFF; + return -1; + } + } + + public int read(char[] b, int off, int len) throws IOException + { + synchronized (lock) + { + if (buf == null) + throw new IOException(); + + /* Don't need to check pos value, arraycopy will check it. */ + if (off < 0 || len < 0 || off + len > b.length) + throw new ArrayIndexOutOfBoundsException(); + + if (pos >= count) + return -1; + + int lastChar = Math.min(count, pos + len); + buf.getChars(pos, lastChar, b, off); + int numChars = lastChar - pos; + pos = lastChar; + return numChars; + } + } + + public boolean ready() // TODO12: throws IOException + { + // TODO12: The JCL specifically says this returns true even if the + // reader has been closed, whereas the online 1.2 doc specifically + // says to throw an IOException if closed. + return true; + } + + public void reset() throws IOException + { + synchronized (lock) + { + if (buf == null) + throw new IOException(); + + pos = markedPos; + } + } + + public long skip(long n) throws IOException + { + synchronized (lock) + { + if (buf == null) + throw new IOException(); + + // Even though the var numChars is a long, in reality it can never + // be larger than an int since the result of subtracting 2 positive + // ints will always fit in an int. Since we have to return a long + // anyway, numChars might as well just be a long. + long numChars = Math.min((long) (count - pos), n < 0 ? 0L : n); + pos += numChars; + return numChars; + } + } +} |