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Diffstat (limited to 'src/java/com/jogamp/common/nio/ByteBufferInputStream.java')
| -rw-r--r-- | src/java/com/jogamp/common/nio/ByteBufferInputStream.java | 183 |
1 files changed, 183 insertions, 0 deletions
diff --git a/src/java/com/jogamp/common/nio/ByteBufferInputStream.java b/src/java/com/jogamp/common/nio/ByteBufferInputStream.java new file mode 100644 index 0000000..5b6f121 --- /dev/null +++ b/src/java/com/jogamp/common/nio/ByteBufferInputStream.java @@ -0,0 +1,183 @@ +/** + * Copyright 2014 JogAmp Community. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without modification, are + * permitted provided that the following conditions are met: + * + * 1. Redistributions of source code must retain the above copyright notice, this list of + * conditions and the following disclaimer. + * + * 2. Redistributions in binary form must reproduce the above copyright notice, this list + * of conditions and the following disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY JogAmp Community ``AS IS'' AND ANY EXPRESS OR IMPLIED + * WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND + * FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL JogAmp Community OR + * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR + * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR + * SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON + * ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING + * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF + * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + * + * The views and conclusions contained in the software and documentation are those of the + * authors and should not be interpreted as representing official policies, either expressed + * or implied, of JogAmp Community. + */ +package com.jogamp.common.nio; + +import java.io.BufferedInputStream; +import java.io.IOException; +import java.io.InputStream; +import java.nio.ByteBuffer; +import java.nio.MappedByteBuffer; +import java.nio.channels.FileChannel; +import java.nio.channels.FileChannel.MapMode; + +/** + * An {@link InputStream} implementation based on an underlying {@link ByteBuffer} + * supporting {@link #markSupported() mark}. + * <p> + * May be utilized as well with a {@link MappedByteBuffer memory-mapped} {@link FileChannel#map(MapMode, long, long) FileChannel} + * using a size ≤ {@link Integer#MAX_VALUE}.<br> + * This becomes efficient with files ≥ 10 MiB, depending on the platform + * and whether the traditional method uses a {@link BufferedInputStream} supporting {@code mark} incl. it's buffer size.<br> + * See test case {@code com.jogamp.common.nio.TestByteBufferInputStream}. + * </p> + * @since 2.3.0 + */ +public class ByteBufferInputStream extends InputStream { + private final ByteBuffer buf; + private int mark; + + /** + * Creates a new byte-buffer input stream. + * + * @param buf the underlying byte buffer. + */ + public ByteBufferInputStream(final ByteBuffer buf) { + this.buf = buf; + this.mark = -1; + } + + @Override + public final int available() { + return buf.remaining(); + } + + /** + * <i>This implementation supports {@code mark}.</i> + * <p> + * {@inheritDoc} + * </p> + */ + @Override + public final boolean markSupported() { + return true; + } + + /** + * <i>This implementation supports {@code mark}.</i> + * <p> + * {@inheritDoc} + * </p> + * @see #markSupported() + */ + @Override + public final synchronized void mark(final int unused) { + mark = buf.position(); + } + + /** + * <i>This implementation supports {@code mark}.</i> + * <p> + * {@inheritDoc} + * </p> + * @see #markSupported() + */ + @Override + public final synchronized void reset() throws IOException { + if ( mark == -1 ) { + throw new IOException(); + } + buf.position(mark); + } + + @Override + public final long skip(final long n) throws IOException { + if( 0 > n ) { + return 0; + } + final int s = (int) Math.min( buf.remaining(), n ); + buf.position(buf.position() + s); + return s; + } + + @Override + public final int read() { + if ( ! buf.hasRemaining() ) { + return -1; + } + return buf.get() & 0xFF; + } + + @Override + public final int read(final byte[] b, final int off, final int len) { + if (b == null) { + throw new NullPointerException(); + } else if (off < 0 || len < 0 || len > b.length - off) { + throw new IndexOutOfBoundsException("offset "+off+", length "+len+", b.length "+b.length); + } + if ( 0 == len ) { + return 0; + } + final int totalRem = buf.remaining(); + if ( 0 == totalRem ) { + return -1; + } + final int maxLen = Math.min(totalRem, len); + if( buf.hasArray() ) { + System.arraycopy(buf.array(), buf.arrayOffset() + buf.position(), b, off, maxLen); + buf.position( buf.position() + maxLen ); + } else { + buf.get(b, off, maxLen); + } + return maxLen; + } + + // @Override + public final int read(final ByteBuffer b, final int len) { + if (b == null) { + throw new NullPointerException(); + } else if (len < 0 || len > b.remaining()) { + throw new IndexOutOfBoundsException("length "+len+", b "+b); + } + if ( 0 == len ) { + return 0; + } + final int remaining = buf.remaining(); + if ( 0 == remaining ) { + return -1; + } + final int maxLen = Math.min(remaining, len); + if( buf.hasArray() && b.hasArray() ) { + System.arraycopy(buf.array(), buf.arrayOffset() + buf.position(), b.array(), b.arrayOffset() + b.position(), maxLen); + buf.position( buf.position() + maxLen ); + b.position( b.position() + maxLen ); + } else if( maxLen == remaining ) { + b.put(buf); + } else { + final int _limit = buf.limit(); + buf.limit(maxLen); + try { + b.put(buf); + } finally { + buf.limit(_limit); + } + } + return maxLen; + } + + public final ByteBuffer getBuffer() { return buf; } +} |