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 * 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.
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of the Apache Software Foundation.  For more
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 */

package org.apache.http.entity;

import java.io.ByteArrayInputStream;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;

import org.apache.http.HttpEntity;
import org.apache.http.util.Args;

A wrapping entity that buffers it content if necessary.
The buffered entity is always repeatable.
If the wrapped entity is repeatable itself, calls are passed through.
If the wrapped entity is not repeatable, the content is read into a
buffer once and provided from there as often as required.
Since:
4.0/**
 * A wrapping entity that buffers it content if necessary.
 * The buffered entity is always repeatable.
 * If the wrapped entity is repeatable itself, calls are passed through.
 * If the wrapped entity is not repeatable, the content is read into a
 * buffer once and provided from there as often as required.
 *
 * @since 4.0
 */
public class BufferedHttpEntity extends HttpEntityWrapper {

    private final byte[] buffer;

    
Creates a new buffered entity wrapper.
Params:
entity –   the entity to wrap, not null
Throws:
IllegalArgumentException – if wrapped is null/**
     * Creates a new buffered entity wrapper.
     *
     * @param entity   the entity to wrap, not null
     * @throws IllegalArgumentException if wrapped is null
     */
    public BufferedHttpEntity(final HttpEntity entity) throws IOException {
        super(entity);
        if (!entity.isRepeatable() || entity.getContentLength() < 0) {
            final ByteArrayOutputStream out = new ByteArrayOutputStream();
            entity.writeTo(out);
            out.flush();
            this.buffer = out.toByteArray();
        } else {
            this.buffer = null;
        }
    }

    @Override
    public long getContentLength() {
        return this.buffer != null ? this.buffer.length : super.getContentLength();
    }

    @Override
    public InputStream getContent() throws IOException {
        return this.buffer != null ? new ByteArrayInputStream(this.buffer) : super.getContent();
    }

    
Tells that this entity does not have to be chunked.
Returns:
 false/**
     * Tells that this entity does not have to be chunked.
     *
     * @return  {@code false}
     */
    @Override
    public boolean isChunked() {
        return (buffer == null) && super.isChunked();
    }

    
Tells that this entity is repeatable.
Returns:
 true/**
     * Tells that this entity is repeatable.
     *
     * @return  {@code true}
     */
    @Override
    public boolean isRepeatable() {
        return true;
    }


    @Override
    public void writeTo(final OutputStream outStream) throws IOException {
        Args.notNull(outStream, "Output stream");
        if (this.buffer != null) {
            outStream.write(this.buffer);
        } else {
            super.writeTo(outStream);
        }
    }


    // non-javadoc, see interface HttpEntity
    @Override
    public boolean isStreaming() {
        return (buffer == null) && super.isStreaming();
    }

} // class BufferedHttpEntity