/*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you 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.apache.axiom.util.blob;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.ArrayList;
import java.util.List;
import org.apache.axiom.ext.io.StreamCopyException;
/**
* Blob implementation that stores data in memory.
*/
public class MemoryBlob implements WritableBlob {
// TODO: this should be configurable
final static int BUFFER_SIZE = 4096;
class OutputStreamImpl extends BlobOutputStream {
public WritableBlob getBlob() {
return MemoryBlob.this;
}
public void write(byte[] b, int off, int len) throws IOException {
int total = 0;
while (total < len) {
int copy = Math.min(len-total, BUFFER_SIZE-index);
System.arraycopy(b, off, currBuffer, index, copy);
total += copy;
index += copy;
off += copy;
if (index >= BUFFER_SIZE) {
addBuffer();
}
}
}
public void write(byte[] b) throws IOException {
this.write(b, 0, b.length);
}
byte[] writeByte = new byte[1];
public void write(int b) throws IOException {
writeByte[0] = (byte) b;
this.write(writeByte, 0, 1);
}
public void close() throws IOException {
outputStream = null;
committed = true;
}
}
class InputStreamImpl extends InputStream {
private int i;
private int currIndex;
private int totalIndex;
private int mark;
private byte[] currBuffer;
private byte[] read_byte = new byte[1];
public InputStreamImpl() {
}
public int read() throws IOException {
int read = read(read_byte);
if (read < 0) {
return -1;
} else {
return read_byte[0] & 0xFF;
}
}
public int available() throws IOException {
return (int)getLength() - totalIndex;
}
public synchronized void mark(int readlimit) {
mark = totalIndex;
}
public boolean markSupported() {
return true;
}
public int read(byte[] b, int off, int len) throws IOException {
int size = (int)getLength();
int total = 0;
if (totalIndex >= size) {
return -1;
}
while (total < len && totalIndex < size) {
if (currBuffer == null) {
currBuffer = (byte[]) data.get(i);
}
int copy = Math.min(len - total, BUFFER_SIZE - currIndex);
copy = Math.min(copy, size - totalIndex);
System.arraycopy(currBuffer, currIndex, b, off, copy);
total += copy;
currIndex += copy;
totalIndex += copy;
off += copy;
if (currIndex >= BUFFER_SIZE) {
if (i+1 < data.size()) {
i++;
currIndex = 0;
} else {
currIndex = BUFFER_SIZE;
}
currBuffer = null;
}
}
return total;
}
public int read(byte[] b) throws IOException {
return this.read(b, 0, b.length);
}
public synchronized void reset() throws IOException {
i = mark / BUFFER_SIZE;
currIndex = mark - (i * BUFFER_SIZE);
currBuffer = (byte[]) data.get(i);
totalIndex = mark;
}
}
List data; // null here indicates the blob is in state NEW
int index;
byte[] currBuffer;
OutputStreamImpl outputStream;
boolean committed;
private void init() {
data = new ArrayList();
addBuffer();
}
void addBuffer() {
currBuffer = new byte[BUFFER_SIZE];
data.add(currBuffer);
index = 0;
}
public boolean isSupportingReadUncommitted() {
return true;
}
public long getLength() {
if (data == null) {
return 0;
} else {
return (BUFFER_SIZE * (data.size()-1)) + index;
}
}
public BlobOutputStream getOutputStream() {
if (data != null) {
throw new IllegalStateException();
} else {
init();
return outputStream = new OutputStreamImpl();
}
}
public long readFrom(InputStream in, long length, boolean commit) throws StreamCopyException {
if (data == null) {
init();
}
if (length == -1) {
length = Long.MAX_VALUE;
}
long bytesReceived = 0;
// Now directly write to the buffers
boolean done = false;
while (!done) {
// Don't get more than will fit in the current buffer
int len = (int) Math.min(BUFFER_SIZE - index, length-bytesReceived);
// Now get the bytes
int bytesRead;
try {
bytesRead = in.read(currBuffer, index, len);
} catch (IOException ex) {
throw new StreamCopyException(StreamCopyException.READ, ex);
}
if (bytesRead >= 0) {
bytesReceived += bytesRead;
index += bytesRead;
if (index >= BUFFER_SIZE) {
addBuffer();
}
if (bytesReceived >= length) {
done = true;
}
} else {
done = true;
}
}
committed = commit;
return bytesReceived;
}
public long readFrom(InputStream in, long length) throws StreamCopyException {
return readFrom(in, length, data == null);
}
public InputStream getInputStream() throws IOException {
return new InputStreamImpl();
}
public void writeTo(OutputStream os) throws StreamCopyException {
int size = (int)getLength();
if (data != null) {
try {
int numBuffers = data.size();
for (int j = 0; j < numBuffers-1; j ++) {
os.write( (byte[]) data.get(j), 0, BUFFER_SIZE);
}
if (numBuffers > 0) {
int writeLimit = size - ((numBuffers-1) * BUFFER_SIZE);
os.write( (byte[]) data.get(numBuffers-1), 0, writeLimit);
}
} catch (IOException ex) {
throw new StreamCopyException(StreamCopyException.WRITE, ex);
}
}
}
public void release() {
// no-op
}
}