1 /* 2 * Copyright (C) 2013 The Android Open Source Project 3 * 4 * Licensed under the Apache License, Version 2.0 (the "License"); 5 * you may not use this file except in compliance with the License. 6 * You may obtain a copy of the License at 7 * 8 * http://www.apache.org/licenses/LICENSE-2.0 9 * 10 * Unless required by applicable law or agreed to in writing, software 11 * distributed under the License is distributed on an "AS IS" BASIS, 12 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 13 * See the License for the specific language governing permissions and 14 * limitations under the License. 15 */ 16 package com.android.loganalysis.util; 17 18 import java.util.HashSet; 19 import java.util.Set; 20 import java.util.regex.Matcher; 21 import java.util.regex.Pattern; 22 23 /** 24 * A utility class for matching a message against a set of patterns. 25 * <p> 26 * This is used to match a message against a set of patterns, and optionally, an extra object. If 27 * the message is matched, a category will be returned. This means that a single object can be used 28 * to match many different categories. 29 */ 30 public class LogPatternUtil { 31 32 /** 33 * A class used to store pattern, extras, and category. 34 */ 35 private class PatternInfo { 36 public Pattern mPattern; 37 public Object mExtras; 38 public String mCategory; 39 40 /** 41 * Constructor for {@link PatternInfo} 42 * 43 * @param pattern the {@link Pattern} to match against. 44 * @param extras the {@link Object} to additionally match against. If extras is null, it 45 * will be treated as wildcard 46 * @param category the category to return if there is a match. 47 */ PatternInfo(Pattern pattern, Object extras, String category)48 public PatternInfo(Pattern pattern, Object extras, String category) { 49 mPattern = pattern; 50 mExtras = extras; 51 mCategory = category; 52 } 53 } 54 55 private Set<PatternInfo> mPatterns = new HashSet<PatternInfo>(); 56 57 /** 58 * Add a pattern to this list of patterns to match against. 59 * 60 * @param pattern the {@link Pattern} object to match against. 61 * @param category the category to return if there is a match. 62 */ addPattern(Pattern pattern, String category)63 public void addPattern(Pattern pattern, String category) { 64 addPattern(pattern, null, category); 65 } 66 67 /** 68 * Add a pattern to this list of patterns to match against. 69 * 70 * @param pattern the {@link Pattern} to match against. 71 * @param extras the {@link Object} to additionally match against. If extras is null, it will 72 * be treated as wildcard 73 * @param category the category to return if there is a match. 74 */ addPattern(Pattern pattern, Object extras, String category)75 public void addPattern(Pattern pattern, Object extras, String category) { 76 mPatterns.add(new PatternInfo(pattern, extras, category)); 77 } 78 79 /** 80 * Checks to see if the message matches any patterns. 81 * 82 * @param message the message to match against 83 * @return The category of the match. 84 */ checkMessage(String message)85 public String checkMessage(String message) { 86 return checkMessage(message, null); 87 } 88 89 /** 90 * Checks to see if the message matches any patterns. 91 * 92 * @param message the message to match against 93 * @param extras the extras to match against 94 * @return The category of the match. 95 */ checkMessage(String message, Object extras)96 public String checkMessage(String message, Object extras) { 97 for (PatternInfo patternInfo : mPatterns) { 98 Matcher m = patternInfo.mPattern.matcher(message); 99 100 // Return the category if the pattern matches and the extras are equal. Treat a null 101 // patternInfo.mExtras as a wildcard. 102 if (m.matches() && 103 (patternInfo.mExtras == null || patternInfo.mExtras.equals(extras))) { 104 return patternInfo.mCategory; 105 } 106 } 107 return null; 108 } 109 } 110