1 /* 2 * Licensed to the Apache Software Foundation (ASF) under one or more 3 * contributor license agreements. See the NOTICE file distributed with 4 * this work for additional information regarding copyright ownership. 5 * The ASF licenses this file to You under the Apache License, Version 2.0 6 * (the "License"); you may not use this file except in compliance with 7 * the License. You may obtain a copy of the License at 8 * 9 * http://www.apache.org/licenses/LICENSE-2.0 10 * 11 * Unless required by applicable law or agreed to in writing, software 12 * distributed under the License is distributed on an "AS IS" BASIS, 13 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 14 * See the License for the specific language governing permissions and 15 * limitations under the License. 16 */ 17 package org.apache.commons.io.input; 18 19 import java.io.Reader; 20 import java.util.Arrays; 21 import java.util.Collections; 22 import java.util.HashSet; 23 import java.util.Set; 24 import java.util.function.IntPredicate; 25 26 /** 27 * A filter reader that removes a given set of characters represented as {@code int} code points, handy to remove known 28 * junk characters from CSV files for example. 29 * <p> 30 * This class must convert each {@code int} read to an {@link Integer}. You can increase the Integer cache with a system 31 * property, see {@link Integer}. 32 * </p> 33 */ 34 public class CharacterSetFilterReader extends AbstractCharacterFilterReader { 35 toIntPredicate(final Set<Integer> skip)36 private static IntPredicate toIntPredicate(final Set<Integer> skip) { 37 if (skip == null) { 38 return SKIP_NONE; 39 } 40 final Set<Integer> unmodifiableSet = Collections.unmodifiableSet(skip); 41 return c -> unmodifiableSet.contains(Integer.valueOf(c)); 42 } 43 44 /** 45 * Constructs a new reader. 46 * 47 * @param reader the reader to filter. 48 * @param skip the set of characters to filter out. 49 * @since 2.9.0 50 */ CharacterSetFilterReader(final Reader reader, final Integer... skip)51 public CharacterSetFilterReader(final Reader reader, final Integer... skip) { 52 this(reader, new HashSet<>(Arrays.asList(skip))); 53 } 54 55 /** 56 * Constructs a new reader. 57 * 58 * @param reader the reader to filter. 59 * @param skip the set of characters to filter out. 60 */ CharacterSetFilterReader(final Reader reader, final Set<Integer> skip)61 public CharacterSetFilterReader(final Reader reader, final Set<Integer> skip) { 62 super(reader, toIntPredicate(skip)); 63 } 64 65 } 66