/*
* $Header: /home/jerenkrantz/tmp/commons/commons-convert/cvs/home/cvs/jakarta-commons//httpclient/src/java/org/apache/commons/httpclient/util/EncodingUtil.java,v 1.8 2004/05/13 04:01:22 mbecke Exp $
* $Revision: 480424 $
* $Date: 2006-11-29 06:56:49 +0100 (Wed, 29 Nov 2006) $
*
* ====================================================================
*
* 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.commons.httpclient.util;
import java.io.UnsupportedEncodingException;
import org.apache.commons.codec.net.URLCodec;
import org.apache.commons.httpclient.HttpClientError;
import org.apache.commons.httpclient.NameValuePair;
import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;
/**
* The home for utility methods that handle various encoding tasks.
*
* @author Michael Becke
* @author <a href="mailto:oleg@ural.ru">Oleg Kalnichevski</a>
*
* @since 2.0 final
*/
public class EncodingUtil {
/** Default content encoding chatset */
private static final String DEFAULT_CHARSET = "ISO-8859-1";
/** Log object for this class. */
private static final Log LOG = LogFactory.getLog(EncodingUtil.class);
/**
* Form-urlencoding routine.
*
* The default encoding for all forms is `application/x-www-form-urlencoded'.
* A form data set is represented in this media type as follows:
*
* The form field names and values are escaped: space characters are replaced
* by `+', and then reserved characters are escaped as per [URL]; that is,
* non-alphanumeric characters are replaced by `%HH', a percent sign and two
* hexadecimal digits representing the ASCII code of the character. Line breaks,
* as in multi-line text field values, are represented as CR LF pairs, i.e. `%0D%0A'.
*
* <p>
* if the given charset is not supported, ISO-8859-1 is used instead.
* </p>
*
* @param pairs the values to be encoded
* @param charset the character set of pairs to be encoded
*
* @return the urlencoded pairs
*
* @since 2.0 final
*/
public static String formUrlEncode(NameValuePair[] pairs, String charset) {
try {
return doFormUrlEncode(pairs, charset);
} catch (UnsupportedEncodingException e) {
LOG.error("Encoding not supported: " + charset);
try {
return doFormUrlEncode(pairs, DEFAULT_CHARSET);
} catch (UnsupportedEncodingException fatal) {
// Should never happen. ISO-8859-1 must be supported on all JVMs
throw new HttpClientError("Encoding not supported: " +
DEFAULT_CHARSET);
}
}
}
/**
* Form-urlencoding routine.
*
* The default encoding for all forms is `application/x-www-form-urlencoded'.
* A form data set is represented in this media type as follows:
*
* The form field names and values are escaped: space characters are replaced
* by `+', and then reserved characters are escaped as per [URL]; that is,
* non-alphanumeric characters are replaced by `%HH', a percent sign and two
* hexadecimal digits representing the ASCII code of the character. Line breaks,
* as in multi-line text field values, are represented as CR LF pairs, i.e. `%0D%0A'.
*
* @param pairs the values to be encoded
* @param charset the character set of pairs to be encoded
*
* @return the urlencoded pairs
* @throws UnsupportedEncodingException if charset is not supported
*
* @since 2.0 final
*/
private static String doFormUrlEncode(NameValuePair[] pairs, String charset)
throws UnsupportedEncodingException
{
StringBuffer buf = new StringBuffer();
for (int i = 0; i < pairs.length; i++) {
URLCodec codec = new URLCodec();
NameValuePair pair = pairs[i];
if (pair.getName() != null) {
if (i > 0) {
buf.append("&");
}
buf.append(codec.encode(pair.getName(), charset));
buf.append("=");
if (pair.getValue() != null) {
buf.append(codec.encode(pair.getValue(), charset));
}
}
}
return buf.toString();
}
/**
* Converts the byte array of HTTP content characters to a string. If
* the specified charset is not supported, default system encoding
* is used.
*
* @param data the byte array to be encoded
* @param offset the index of the first byte to encode
* @param length the number of bytes to encode
* @param charset the desired character encoding
* @return The result of the conversion.
*
* @since 3.0
*/
public static String getString(
final byte[] data,
int offset,
int length,
String charset
) {
if (data == null) {
throw new IllegalArgumentException("Parameter may not be null");
}
if (charset == null || charset.length() == 0) {
throw new IllegalArgumentException("charset may not be null or empty");
}
try {
return new String(data, offset, length, charset);
} catch (UnsupportedEncodingException e) {
if (LOG.isWarnEnabled()) {
LOG.warn("Unsupported encoding: " + charset + ". System encoding used");
}
return new String(data, offset, length);
}
}
/**
* Converts the byte array of HTTP content characters to a string. If
* the specified charset is not supported, default system encoding
* is used.
*
* @param data the byte array to be encoded
* @param charset the desired character encoding
* @return The result of the conversion.
*
* @since 3.0
*/
public static String getString(final byte[] data, String charset) {
return getString(data, 0, data.length, charset);
}
/**
* Converts the specified string to a byte array. If the charset is not supported the
* default system charset is used.
*
* @param data the string to be encoded
* @param charset the desired character encoding
* @return The resulting byte array.
*
* @since 3.0
*/
public static byte[] getBytes(final String data, String charset) {
if (data == null) {
throw new IllegalArgumentException("data may not be null");
}
if (charset == null || charset.length() == 0) {
throw new IllegalArgumentException("charset may not be null or empty");
}
try {
return data.getBytes(charset);
} catch (UnsupportedEncodingException e) {
if (LOG.isWarnEnabled()) {
LOG.warn("Unsupported encoding: " + charset + ". System encoding used.");
}
return data.getBytes();
}
}
/**
* Converts the specified string to byte array of ASCII characters.
*
* @param data the string to be encoded
* @return The string as a byte array.
*
* @since 3.0
*/
public static byte[] getAsciiBytes(final String data) {
if (data == null) {
throw new IllegalArgumentException("Parameter may not be null");
}
try {
return data.getBytes("US-ASCII");
} catch (UnsupportedEncodingException e) {
throw new HttpClientError("HttpClient requires ASCII support");
}
}
/**
* Converts the byte array of ASCII characters to a string. This method is
* to be used when decoding content of HTTP elements (such as response
* headers)
*
* @param data the byte array to be encoded
* @param offset the index of the first byte to encode
* @param length the number of bytes to encode
* @return The string representation of the byte array
*
* @since 3.0
*/
public static String getAsciiString(final byte[] data, int offset, int length) {
if (data == null) {
throw new IllegalArgumentException("Parameter may not be null");
}
try {
return new String(data, offset, length, "US-ASCII");
} catch (UnsupportedEncodingException e) {
throw new HttpClientError("HttpClient requires ASCII support");
}
}
/**
* Converts the byte array of ASCII characters to a string. This method is
* to be used when decoding content of HTTP elements (such as response
* headers)
*
* @param data the byte array to be encoded
* @return The string representation of the byte array
*
* @since 3.0
*/
public static String getAsciiString(final byte[] data) {
return getAsciiString(data, 0, data.length);
}
/**
* This class should not be instantiated.
*/
private EncodingUtil() {
}
}