001/*
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.commons.text.translate;
018
019import java.io.IOException;
020import java.io.Writer;
021
022/**
023 * Helper subclass to CharSequenceTranslator to remove unpaired surrogates.
024 *
025 * @since 1.0
026 */
027public class UnicodeUnpairedSurrogateRemover extends CodePointTranslator {
028    /**
029     * Implementation of translate that throws out unpaired surrogates. 
030     * {@inheritDoc}
031     */
032    @Override
033    public boolean translate(final int codepoint, final Writer out) throws IOException {
034        if (codepoint >= Character.MIN_SURROGATE && codepoint <= Character.MAX_SURROGATE) {
035            // It's a surrogate. Write nothing and say we've translated.
036            return true;
037        }
038        // It's not a surrogate. Don't translate it.
039        return false;
040    }
041}
042