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/*
* Copyright (c) 2001-2017, Zoltan Farkas All Rights Reserved.
*
* 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 General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*
* Additionally licensed with:
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.spf4j.io;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.io.Writer;
import org.spf4j.recyclable.impl.ArraySuppliers;
/**
*
* @author zoly
*/
public final class Streams {
private Streams() {
}
/**
* see copy(final InputStream is, final OutputStream os, final int buffSize) for detail.
*
* @param is
* @param os
* @return
* @throws IOException
*/
public static long copy(final InputStream is, final OutputStream os) throws IOException {
return copy(is, os, 8192);
}
/**
* Equivalent to guava ByteStreams.copy, with one special behavior: if is has no bytes immediately available for read,
* the os is flushed prior to the next read that will probably block.
*
* I believe this behavior will yield better performance in most scenarios. This method also makes use of:
* Arrays.getBytesTmp. THis method should not be invoked from any context making use of Arrays.getBytesTmp.
*
* @param is
* @param os
* @param buffSize
* @throws IOException
*/
public static long copy(final InputStream is, final OutputStream os, final int buffSize) throws IOException {
if (buffSize < 2) {
int val;
long count = 0;
while ((val = is.read()) >= 0) {
os.write(val);
count++;
}
return count;
}
long total = 0;
byte[] buffer = ArraySuppliers.Bytes.TL_SUPPLIER.get(buffSize);
try {
boolean done = false;
long bytesCopiedSinceLastFlush = 0;
while (true) {
// non-blocking(if input is implemented correctly) read+write as long as data is available.
while (is.available() > 0) {
int nrRead = is.read(buffer, 0, buffSize);
if (nrRead < 0) {
done = true;
break;
} else {
os.write(buffer, 0, nrRead);
total += nrRead;
bytesCopiedSinceLastFlush += nrRead;
}
}
// there seems to be nothing available to read anymore,
// lets flush the os instead of blocking for another read.
if (bytesCopiedSinceLastFlush > 0) {
os.flush();
bytesCopiedSinceLastFlush = 0;
}
if (done) {
break;
}
// most likely a blocking read.
int nrRead = is.read(buffer, 0, buffSize);
if (nrRead < 0) {
break;
} else {
os.write(buffer, 0, nrRead);
total += nrRead;
bytesCopiedSinceLastFlush += nrRead;
}
}
} finally {
ArraySuppliers.Bytes.TL_SUPPLIER.recycle(buffer);
}
return total;
}
public static long copy(final InputStream is, final OutputStream os, final int buffSize, final long maxBytes)
throws IOException {
if (buffSize < 2) {
int val;
long count = 0;
while (count < maxBytes && (val = is.read()) >= 0) {
os.write(val);
count++;
}
return count;
}
long count = 0;
byte[] buffer = ArraySuppliers.Bytes.TL_SUPPLIER.get(buffSize);
try {
boolean done = false;
long bytesCopiedSinceLastFlush = 0;
while (true) {
// non-blocking(if input is implemented correctly) read+write as long as data is available.
while (is.available() > 0) {
long left = maxBytes - count;
int toRead = Math.min(buffSize, left > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) left);
int nrRead = is.read(buffer, 0, toRead);
if (nrRead < 0) {
done = true;
break;
} else {
os.write(buffer, 0, nrRead);
count += nrRead;
bytesCopiedSinceLastFlush += nrRead;
}
if (count >= maxBytes) {
done = true;
break;
}
}
// there seems to be nothing available to read anymore,
// lets flush the os instead of blocking for another read.
if (bytesCopiedSinceLastFlush > 0) {
os.flush();
bytesCopiedSinceLastFlush = 0;
}
if (done) {
break;
}
// most likely a blocking read.
long left = maxBytes - count;
int toRead = Math.min(buffSize, left > Integer.MAX_VALUE ? Integer.MAX_VALUE : (int) left);
int nrRead = is.read(buffer, 0, toRead);
if (nrRead < 0) {
break;
} else {
os.write(buffer, 0, nrRead);
count += nrRead;
bytesCopiedSinceLastFlush += nrRead;
}
if (count >= maxBytes) {
done = true;
break;
}
}
} finally {
ArraySuppliers.Bytes.TL_SUPPLIER.recycle(buffer);
}
return count;
}
/**
* faster variant than guava CharStreams.asWriter.
*
* @param appendable - the appendable to transform.
* @return - the writer that will write to the appendable.
*/
public static Writer asWriter(final Appendable appendable) {
if (appendable instanceof Writer) {
return (Writer) appendable;
} else {
return new AppendableWriter(appendable);
}
}
}