/*
* JBoss, Home of Professional Open Source.
* See the COPYRIGHT.txt file distributed with this work for information
* regarding copyright ownership. Some portions may be licensed
* to Red Hat, Inc. under one or more contributor license agreements.
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
* License as published by the Free Software Foundation; either
* version 2.1 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
* 02110-1301 USA.
*/
/**
*
*/
package org.teiid.core.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStreamWriter;
import java.io.Reader;
import java.io.Writer;
import java.nio.charset.Charset;
import org.teiid.core.types.DataTypeManager;
/**
* Implements a buffered {@link InputStream} for a given {@link Reader} and {@link Charset}
*/
public class ReaderInputStream extends InputStream {
//even though we're dealing with chars, we'll use the same default
private static final int DEFAULT_BUFFER_SIZE = DataTypeManager.MAX_LOB_MEMORY_BYTES;
private final Reader reader;
private Writer writer;
private char[] charBuffer;
private AccessibleByteArrayOutputStream out = new AccessibleByteArrayOutputStream();
private boolean hasMore = true;
private int pos;
public ReaderInputStream(Reader reader, Charset charset) {
this(reader, charset, DEFAULT_BUFFER_SIZE);
}
public ReaderInputStream(Reader reader, Charset charset, int bufferSize) {
this.reader = reader;
this.writer = new OutputStreamWriter(out, charset);
this.charBuffer = new char[bufferSize];
}
@Override
public int read() throws IOException {
while (pos >= out.getCount()) {
if (!hasMore) {
return -1;
}
out.reset();
pos = 0;
int charsRead = reader.read(charBuffer);
if (charsRead == -1) {
writer.close();
hasMore = false;
continue;
}
writer.write(charBuffer, 0, charsRead);
writer.flush();
}
return out.getBuffer()[pos++] & 0xff;
}
@Override
public void close() throws IOException {
this.reader.close();
}
}