content: /*
   * Licensed to the Apache Software Foundation (ASF) under one
   * or more contributor license agreements.  See the NOTICE file
   * distributed with this work for additional information
   * regarding copyright ownership.  The ASF licenses this file
   * to you 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.
   */
  package org.apache.beam.sdk.testing;
  
  import java.util.regex.Pattern;
  import org.hamcrest.BaseMatcher;
  import org.hamcrest.Description;
  
  /** Hamcrest matcher to assert a string matches a pattern. */
  public class RegexMatcher extends BaseMatcher<String> {
    private final Pattern pattern;
  
    public RegexMatcher(String regex) {
      this.pattern = Pattern.compile(regex);
    }
  
    @Override
    public boolean matches(Object o) {
      if (!(o instanceof String)) {
        return false;
      }
      return pattern.matcher((String) o).matches();
    }
  
    @Override
    public void describeTo(Description description) {
      description.appendText(String.format("matches regular expression %s", pattern));
    }
  
    public static RegexMatcher matches(String regex) {
      return new RegexMatcher(regex);
    }
  }
  