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.functor.example.kata.four;
18
19 import org.apache.commons.functor.UnaryPredicate;
20
21 /**
22 * Tests to true iff the input object can be converted to
23 * an Integer by {@link ToInteger}.
24 *
25 * @version $Revision: 665786 $ $Date: 2008-06-09 19:17:39 +0200 (Mon, 09 Jun 2008) $
26 * @author Rodney Waldhoff
27 */
28 public final class IsInteger implements UnaryPredicate<String> {
29 public boolean test(String obj) {
30 try {
31 ToInteger.instance().evaluate(obj);
32 return true;
33 } catch(RuntimeException e){
34 return false;
35 }
36 }
37
38 public static final IsInteger instance() {
39 return INSTANCE;
40 }
41
42 private static final IsInteger INSTANCE = new IsInteger();
43 }