1/*
2 * Copyright (C) 2010 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
17package vogar.target;
18
19import java.io.IOException;
20import java.util.Arrays;
21import java.util.Collections;
22import java.util.Set;
23
24class ClassFinder {
25    /**
26     * Returns either a Set with the class represented by classOrPackageName as its only element, if
27     * classOrPackageName represents a class, or a Set containing all of the classes contained
28     * within the package represented by classOrPackageName, if it represents a package.
29     *
30     * Throws an exception if it represents neither a class nor a package with at least one class.
31     */
32    public Set<Class<?>> find(String classOrPackageName) {
33        try {
34            // if no exception thrown, classOrPackageName must represent a class
35            return Collections.<Class<?>>singleton(Class.forName(classOrPackageName));
36        } catch (ClassNotFoundException e) {
37        }
38        // classOrPackageName might represent a package
39        try {
40            Package aPackage = new ClassPathScanner().scan(classOrPackageName);
41            Set<Class<?>> classes = aPackage.getTopLevelClassesRecursive();
42            if (classes.isEmpty()) {
43                throw new IllegalArgumentException("No classes in package: " + classOrPackageName +
44                        "; classpath is " + Arrays.toString(ClassPathScanner.getClassPath()));
45            }
46            return classes;
47        } catch (IOException eIO) {
48            throw new RuntimeException(eIO);
49        }
50    }
51}
52