Java tutorial
//package com.java2s; /* * Copyright (C) 2014 The Android Open Source Project * * 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.util.regex.Matcher; import java.util.regex.Pattern; public class Main { public static String parseOptionalStringAttr(String line, Pattern pattern) { Matcher matcher = pattern.matcher(line); if (matcher.find() && matcher.groupCount() == 1) { return matcher.group(1); } return null; } }