Java tutorial
//package com.java2s; /* * Copyright (c) 2013. wyouflf (wyouflf@gmail.com) * * Licensed 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. */ import java.nio.ByteBuffer; import java.nio.CharBuffer; import java.nio.charset.Charset; public class Main { /** * Decode/unescape a portion of a URL, to use with the query part ensure {@code plusAsBlank} is true. * * @param content the portion to decode * @param charset the charset to use * @param plusAsBlank if {@code true}, then convert '+' to space (e.g. for www-url-form-encoded content), otherwise leave as is. * @return encoded string */ private static String urldecode(final String content, final Charset charset, final boolean plusAsBlank) { if (content == null) { return null; } ByteBuffer bb = ByteBuffer.allocate(content.length()); CharBuffer cb = CharBuffer.wrap(content); while (cb.hasRemaining()) { char c = cb.get(); if (c == '%' && cb.remaining() >= 2) { char uc = cb.get(); char lc = cb.get(); int u = Character.digit(uc, 16); int l = Character.digit(lc, 16); if (u != -1 && l != -1) { bb.put((byte) ((u << 4) + l)); } else { bb.put((byte) '%'); bb.put((byte) uc); bb.put((byte) lc); } } else if (plusAsBlank && c == '+') { bb.put((byte) ' '); } else { bb.put((byte) c); } } bb.flip(); return charset.decode(bb).toString(); } }