/*
* ====================================================================
* 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
* information on the Apache Software Foundation, please see
* <http://www.apache.org/>.
*
*/
package org.apache.http.util;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.Reader;
import org.apache.http.HeaderElement;
import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.protocol.HTTP;
/**
* Static helpers for dealing with {@link HttpEntity}s.
*
* @since 4.0
*/
public final class EntityUtils {
private EntityUtils() {
}
/**
* Read the contents of an entity and return it as a byte array.
*
* @param entity
* @return byte array containing the entity content. May be empty; never null.
* @throws IOException if an error occurs reading the input stream
* @throws IllegalArgumentException if entity is null or if content length > Integer.MAX_VALUE
*/
public static byte[] toByteArray(final HttpEntity entity) throws IOException {
if (entity == null) {
throw new IllegalArgumentException("HTTP entity may not be null");
}
InputStream instream = entity.getContent();
if (instream == null) {
return new byte[] {};
}
if (entity.getContentLength() > Integer.MAX_VALUE) {
throw new IllegalArgumentException("HTTP entity too large to be buffered in memory");
}
int i = (int)entity.getContentLength();
if (i < 0) {
i = 4096;
}
ByteArrayBuffer buffer = new ByteArrayBuffer(i);
try {
byte[] tmp = new byte[4096];
int l;
while((l = instream.read(tmp)) != -1) {
buffer.append(tmp, 0, l);
}
} finally {
instream.close();
}
return buffer.toByteArray();
}
/**
* Obtains character set of the entity, if known.
*
* @param entity must not be null
* @return the character set, or null if not found
* @throws ParseException if header elements cannot be parsed
* @throws IllegalArgumentException if entity is null
*/
public static String getContentCharSet(final HttpEntity entity) throws ParseException {
if (entity == null) {
throw new IllegalArgumentException("HTTP entity may not be null");
}
String charset = null;
if (entity.getContentType() != null) {
HeaderElement values[] = entity.getContentType().getElements();
if (values.length > 0) {
NameValuePair param = values[0].getParameterByName("charset");
if (param != null) {
charset = param.getValue();
}
}
}
return charset;
}
/**
* Obtains mime type of the entity, if known.
*
* @param entity must not be null
* @return the character set, or null if not found
* @throws ParseException if header elements cannot be parsed
* @throws IllegalArgumentException if entity is null
*
* @since 4.1
*/
public static String getContentMimeType(final HttpEntity entity) throws ParseException {
if (entity == null) {
throw new IllegalArgumentException("HTTP entity may not be null");
}
String mimeType = null;
if (entity.getContentType() != null) {
HeaderElement values[] = entity.getContentType().getElements();
if (values.length > 0) {
mimeType = values[0].getName();
}
}
return mimeType;
}
/**
* Get the entity content as a String, using the provided default character set
* if none is found in the entity.
* If defaultCharset is null, the default "ISO-8859-1" is used.
*
* @param entity must not be null
* @param defaultCharset character set to be applied if none found in the entity
* @return the entity content as a String
* @throws ParseException if header elements cannot be parsed
* @throws IllegalArgumentException if entity is null or if content length > Integer.MAX_VALUE
* @throws IOException if an error occurs reading the input stream
*/
public static String toString(
final HttpEntity entity, final String defaultCharset) throws IOException, ParseException {
if (entity == null) {
throw new IllegalArgumentException("HTTP entity may not be null");
}
InputStream instream = entity.getContent();
if (instream == null) {
return "";
}
if (entity.getContentLength() > Integer.MAX_VALUE) {
throw new IllegalArgumentException("HTTP entity too large to be buffered in memory");
}
int i = (int)entity.getContentLength();
if (i < 0) {
i = 4096;
}
String charset = getContentCharSet(entity);
if (charset == null) {
charset = defaultCharset;
}
if (charset == null) {
charset = HTTP.DEFAULT_CONTENT_CHARSET;
}
Reader reader = new InputStreamReader(instream, charset);
CharArrayBuffer buffer = new CharArrayBuffer(i);
try {
char[] tmp = new char[1024];
int l;
while((l = reader.read(tmp)) != -1) {
buffer.append(tmp, 0, l);
}
} finally {
reader.close();
}
return buffer.toString();
}
/**
* Read the contents of an entity and return it as a String.
* The content is converted using the character set from the entity (if any),
* failing that, "ISO-8859-1" is used.
*
* @param entity
* @return String containing the content.
* @throws ParseException if header elements cannot be parsed
* @throws IllegalArgumentException if entity is null or if content length > Integer.MAX_VALUE
* @throws IOException if an error occurs reading the input stream
*/
public static String toString(final HttpEntity entity)
throws IOException, ParseException {
return toString(entity, null);
}
}