flex.messaging.util.URLEncoder Maven / Gradle / Ivy
/*
* 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 flex.messaging.util;
import java.io.BufferedWriter;
import java.io.ByteArrayOutputStream;
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException;
/**
* Utility class for URL encoding.
*
*
*/
public final class URLEncoder
{
public static String charset = "UTF8";
private URLEncoder()
{
}
public static String encode(String s)
{
try
{
return encode(s, charset);
}
catch (UnsupportedEncodingException ex)
{
throw new IllegalArgumentException(charset);
}
}
public static String encode(String s, String enc) throws UnsupportedEncodingException
{
if (!needsEncoding(s))
{
return s;
}
int length = s.length();
StringBuffer out = new StringBuffer(length);
ByteArrayOutputStream buf = new ByteArrayOutputStream(10); // why 10? w3c says so.
BufferedWriter writer = new BufferedWriter(new OutputStreamWriter(buf, enc));
for (int i = 0; i < length; i++)
{
int c = (int)s.charAt(i);
if (c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9' || c == ' ')
{
if (c == ' ')
{
c = '+';
}
toHex(out, buf.toByteArray());
buf.reset();
out.append((char)c);
}
else
{
try
{
writer.write(c);
if (c >= 0xD800 && c <= 0xDBFF && i < length - 1)
{
int d = (int)s.charAt(i + 1);
if (d >= 0xDC00 && d <= 0xDFFF)
{
writer.write(d);
i++;
}
}
writer.flush();
}
catch (IOException ex)
{
throw new IllegalArgumentException(s);
}
}
}
try
{
writer.close();
}
catch (IOException ioe)
{
// Ignore exceptions on close.
}
toHex(out, buf.toByteArray());
return out.toString();
}
private static void toHex(StringBuffer buffer, byte[] b)
{
for (int i = 0; i < b.length; i++)
{
buffer.append('%');
char ch = Character.forDigit((b[i] >> 4) & 0xF, 16);
if (Character.isLetter(ch))
{
ch -= 32;
}
buffer.append(ch);
ch = Character.forDigit(b[i] & 0xF, 16);
if (Character.isLetter(ch))
{
ch -= 32;
}
buffer.append(ch);
}
}
private static boolean needsEncoding(String s)
{
if (s == null)
return false;
for (int i = 0; i < s.length(); i++)
{
int c = (int)s.charAt(i);
if (!(c >= 'a' && c <= 'z' || c >= 'A' && c <= 'Z' || c >= '0' && c <= '9'))
return true;
// Otherwise, keep going
}
return false;
}
}