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[ADD] TTFDataStream.createSubView() to create a subview without copying arrays
[ADD] RandomAccessReadUncachedDataStream that doesn't read input stream to byte[]
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6 files changed

+294
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lines changed

6 files changed

+294
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lines changed

‎fontbox/src/main/java/org/apache/fontbox/ttf/NameRecord.java

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@@ -180,6 +180,7 @@ void initData( TrueTypeFont ttf, TTFDataStream data ) throws IOException
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*
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* @return A string for this class.
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*/
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@Override
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public String toString()
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{
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return

‎fontbox/src/main/java/org/apache/fontbox/ttf/RandomAccessReadDataStream.java

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@@ -19,9 +19,12 @@
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import java.io.ByteArrayInputStream;
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import java.io.IOException;
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import java.io.InputStream;
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import java.util.logging.Level;
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import java.util.logging.Logger;
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import org.apache.pdfbox.io.IOUtils;
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import org.apache.pdfbox.io.RandomAccessRead;
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import org.apache.pdfbox.io.RandomAccessReadBuffer;
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/**
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* An implementation of the TTFDataStream using RandomAccessRead as source.
@@ -174,6 +177,20 @@ public int read(byte[] b, int off, int len) throws IOException
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return bytesToRead;
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}
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@Override
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public RandomAccessRead createSubView(long length)
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{
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try
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{
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return new RandomAccessReadBuffer(data).createView(currentPosition, length);
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}
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catch (IOException ex)
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{
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Logger.getLogger(RandomAccessReadDataStream.class.getName()).log(Level.SEVERE, null, ex);
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return null;
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}
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}
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/**
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* {@inheritDoc}
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*/

‎fontbox/src/main/java/org/apache/fontbox/ttf/RandomAccessReadUnbufferedDataStream.java

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@@ -0,0 +1,188 @@
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/*
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* Licensed to the Apache Software Foundation (ASF) under one or more
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* contributor license agreements. See the NOTICE file distributed with
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* this work for additional information regarding copyright ownership.
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* The ASF licenses this file to You under the Apache License, Version 2.0
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* (the "License"); you may not use this file except in compliance with
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* the License. You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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package org.apache.fontbox.ttf;
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import java.io.IOException;
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import java.io.InputStream;
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import org.apache.pdfbox.io.RandomAccessRead;
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import org.apache.pdfbox.io.RandomAccessReadView;
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/**
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* In contrast to {@link RandomAccessReadDataStream},
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* this class doesn't pre-load {@code RandomAccessRead} into a {@code byte[]},
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* it works with {@link RandomAccessRead} directly.
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*
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* Performance: it is much faster if most of the buffer is skipped, and slower if whole buffer is read()
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*/
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class RandomAccessReadUnbufferedDataStream extends TTFDataStream
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{
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private final long length;
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private final RandomAccessRead randomAccessRead;
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/**
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* @throws IOException If there is a problem reading the source length.
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*/
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RandomAccessReadUnbufferedDataStream(RandomAccessRead randomAccessRead) throws IOException
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{
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this.length = randomAccessRead.length();
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this.randomAccessRead = randomAccessRead;
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public long getCurrentPosition() throws IOException
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{
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return randomAccessRead.getPosition();
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}
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/**
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* Close the underlying resources.
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*
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* @throws IOException If there is an error closing the resources.
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*/
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@Override
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public void close() throws IOException
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{
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randomAccessRead.close();
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public int read() throws IOException
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{
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return randomAccessRead.read();
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public final long readLong() throws IOException
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{
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return ((long) readInt() << 32) | (readInt() & 0xFFFFFFFFL);
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}
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/**
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* {@inheritDoc}
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*/
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private int readInt() throws IOException
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{
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int b1 = read();
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int b2 = read();
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int b3 = read();
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int b4 = read();
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return (b1 << 24) | (b2 << 16) | (b3 << 8) | b4;
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public void seek(long pos) throws IOException
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{
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randomAccessRead.seek(pos);
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public int read(byte[] b, int off, int len) throws IOException
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{
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randomAccessRead.readExact(b, off, len);
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return len;
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}
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/**
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* Lifetime of returned InputStream is bound by {@code this} lifetime, it won't close underlying {@code RandomAccessRead}.
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*
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* {@inheritDoc}
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*/
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@Override
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public InputStream getOriginalData() throws IOException
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{
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return new RandomAccessReadNonClosingInputStream(randomAccessRead.createView(0, length));
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}
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/**
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* {@inheritDoc}
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*/
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@Override
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public long getOriginalDataSize()
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{
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return length;
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}
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@Override
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public RandomAccessRead createSubView(long length)
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{
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try
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{
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return randomAccessRead.createView(randomAccessRead.getPosition(), length);
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}
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catch (IOException ex)
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{
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assert false : "Please implement " + randomAccessRead.getClass() + ".createView()";
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return null;
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}
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}
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private static final class RandomAccessReadNonClosingInputStream extends InputStream {
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private final RandomAccessReadView randomAccessRead;
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public RandomAccessReadNonClosingInputStream(RandomAccessReadView randomAccessRead)
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{
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this.randomAccessRead = randomAccessRead;
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}
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@Override
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public int read() throws IOException
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{
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return randomAccessRead.read();
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}
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@Override
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public int read(byte[] b) throws IOException
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{
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return randomAccessRead.read(b);
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}
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@Override
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public int read(byte[] b, int off, int len) throws IOException
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{
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return randomAccessRead.read(b, off, len);
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}
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@Override
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public long skip(long n) throws IOException
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{
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randomAccessRead.seek(randomAccessRead.getPosition() + n);
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return n;
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}
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@Override
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public void close() throws IOException {
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// WARNING: .close() will close RandomAccessReadMemoryMappedFile if this View was based on it
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// randomAccessRead.close();
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}
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}
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}

‎fontbox/src/main/java/org/apache/fontbox/ttf/TTCDataStream.java

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@@ -19,6 +19,7 @@
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import java.io.IOException;
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import java.io.InputStream;
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import org.apache.pdfbox.io.RandomAccessRead;
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2324
/**
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* A wrapper for a TTF stream inside a TTC file, does not close the underlying shared stream.
@@ -83,4 +84,9 @@ public long getOriginalDataSize()
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return stream.getOriginalDataSize();
8485
}
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@Override
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public RandomAccessRead createSubView(long length)
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{
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return stream.createSubView(length);
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}
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}

‎fontbox/src/main/java/org/apache/fontbox/ttf/TTFDataStream.java

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@@ -24,6 +24,7 @@
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import java.nio.charset.StandardCharsets;
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import java.util.Calendar;
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import java.util.TimeZone;
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import org.apache.pdfbox.io.RandomAccessRead;
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/**
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* An abstract class to read a data stream.
@@ -278,6 +279,17 @@ public byte[] read(int numberOfBytes) throws IOException
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*/
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public abstract int read(byte[] b, int off, int len) throws IOException;
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282+
/**
283+
* Creates a view from current position to {@code pos + length}.
284+
* It can be faster than {@code read(length)} if you only need a few bytes.
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* {@code SubView.close()} should never close {@code TTFDataStream.this}, only itself.
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*
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* @return A view or null (caller can use {@link #read} instead). Please close() the result
288+
*/
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public /*@Nullable*/ RandomAccessRead createSubView(long length) {
290+
return null;
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}
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/**
282294
* Get the current position in the stream.
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*

‎io/src/main/java/org/apache/pdfbox/io/RandomAccessRead.java

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@@ -55,7 +55,76 @@ default int read(byte[] b) throws IOException
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* @throws IOException If there was an error while reading the data.
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*/
5757
int read(byte[] b, int offset, int length) throws IOException;
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/**
60+
* Read a buffer of data of exactly {@code length} bytes.
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*
62+
* @throws IOException if less than {@code length} bytes are available
63+
*/
64+
default byte[] readExact(byte[] b, int offset, int length) throws IOException
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{
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if (length() - getPosition() >= length)
67+
{
68+
int read = readUpTo(b, offset, length);
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if (read == length)
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{
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return b;
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}
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rewind(read);
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}
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throw new IOException("End-of-data");
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}
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/**
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* Read a buffer of data of exactly {@code length} bytes.
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*
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* @throws IOException if less than {@code length} bytes are available
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*/
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default byte[] readExact(int length) throws IOException
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{
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return readExact(new byte[length], 0, length);
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}
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/**
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* Finishes when {@code length} bytes are read, or EOF. Always returns {@code result}, never trims.
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* @see InputStream#readNBytes(byte[], int, int)
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* @return when {@code result.length} bytes are read, or EOF
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*/
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default int readUpTo(byte[] result) throws IOException
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{
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return readUpTo(result, 0, result.length);
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}
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/**
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* Finishes when {@code length} bytes are read, or EOF. Just like {@link org.apache.pdfbox.io.IOUtils#populateBuffer(java.io.InputStream, byte[])}
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* @see InputStream#readNBytes(byte[], int, int)
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* @return amount of read bytes
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*/
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default int readUpTo(byte[] result, int offset, int length) throws IOException
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{
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if (Integer.MAX_VALUE - length < offset)
106+
{
107+
throw new IOException("Integer overflow");
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}
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int cursor = offset;
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int end = offset + length;
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while (cursor < end)
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{
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int read = read(result, cursor, end - cursor);
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if (read < 0)
115+
{
116+
break;
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}
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else if (read == 0)
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{
120+
// in order to not get stuck in a loop we check readBytes (this should never happen)
121+
throw new IOException("Read 0 bytes, risk of an infinite loop");
122+
}
123+
cursor += read;
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}
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return cursor - offset;
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}
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/**
60129
* Returns offset of next byte to be returned by a read method.
61130
*

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