package com.atlassian.plugin.util;
   
   import com.atlassian.plugin.test.PluginJarBuilder;
   import junit.framework.TestCase;
   import org.apache.commons.io.IOUtils;
   
   import java.io.IOException;
   import java.net.URL;
   import java.net.URLClassLoader;
  import java.util.Enumeration;
  import java.util.HashMap;
  import java.util.Map;
  
  import static java.util.Collections.singletonMap;
  
  /**
   *
   */
  public class TestChainingClassLoader extends TestCase {
      public void testLoadClassInFirst() throws Exception {
          final ClassLoader cl1 = new PluginJarBuilder().addFormattedJava("my.Foo", "package my; public class Foo {}").getClassLoader();
          final ClassLoader cl2 = new PluginJarBuilder().getClassLoader();
  
          assertEquals(cl1, new ChainingClassLoader(cl1, cl2).loadClass("my.Foo").getClassLoader());
      }
  
      public void testLoadClassInSecond() throws Exception {
          final ClassLoader cl1 = new PluginJarBuilder().getClassLoader();
          final ClassLoader cl2 = new PluginJarBuilder().addFormattedJava("my.Foo", "package my; public class Foo {}").getClassLoader();
  
          assertEquals(cl2, new ChainingClassLoader(cl1, cl2).loadClass("my.Foo").getClassLoader());
      }
  
      public void testLoadClassInFirstHidesSecond() throws Exception {
          final ClassLoader cl1 = new PluginJarBuilder().addFormattedJava("my.Foo", "package my; public class Foo {}").getClassLoader();
          final ClassLoader cl2 = new PluginJarBuilder().addFormattedJava("my.Foo", "package my; public class Foo {}").getClassLoader();
  
          assertEquals(cl1, new ChainingClassLoader(cl1, cl2).loadClass("my.Foo").getClassLoader());
      }
  
      public void testLoadResourceInFirst() throws Exception {
          ClassLoader cl1 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "foo");
          }});
          ClassLoader cl2 = buildClassLoaderWithResources(new HashMap<String, String>() {{
          }});
          ChainingClassLoader ccl = new ChainingClassLoader(cl1, cl2);
          assertEquals("foo", IOUtils.readLines(ccl.getResourceAsStream("my/foo.txt")).get(0));
      }
  
      public void testLoadResourceInSecond() throws Exception {
          ClassLoader cl1 = buildClassLoaderWithResources(new HashMap<String, String>() {{
          }});
          ClassLoader cl2 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "foo");
          }});
          ChainingClassLoader ccl = new ChainingClassLoader(cl1, cl2);
          assertEquals("foo", IOUtils.readLines(ccl.getResourceAsStream("my/foo.txt")).get(0));
      }
  
      public void testLoadResourceInFirstHidesSecond() throws Exception {
          ClassLoader cl1 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "foo");
          }});
          ClassLoader cl2 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "bar");
          }});
          ChainingClassLoader ccl = new ChainingClassLoader(cl1, cl2);
          assertEquals("foo", IOUtils.readLines(ccl.getResourceAsStream("my/foo.txt")).get(0));
      }
  
      public void testLoadResources() throws Exception {
          ClassLoader cl1 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "foo");
          }});
          ClassLoader cl2 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "bar");
          }});
          ChainingClassLoader ccl = new ChainingClassLoader(cl1, cl2);
          Enumeration<URL> e = ccl.getResources("my/foo.txt");
          assertEquals("foo", IOUtils.readLines(e.nextElement().openStream()).get(0));
          assertEquals("bar", IOUtils.readLines(e.nextElement().openStream()).get(0));
      }
  
      public void testLoadResourceWithNameOverride() throws Exception {
          ClassLoader cl1 = buildClassLoaderWithResources(new HashMap<String, String>() {{
              put("my/foo.txt", "foo");
              put("my/bar.txt", "bar");
          }});
          ClassLoader cl2 = buildClassLoaderWithResources(new HashMap<String, String>() {{
          }});
          ChainingClassLoader ccl = new ChainingClassLoader(singletonMap("my/bar.txt", "my/foo.txt"), cl1, cl2);
          assertEquals("foo", IOUtils.readLines(ccl.getResourceAsStream("my/bar.txt")).get(0));
          assertEquals("foo", IOUtils.readLines(ccl.getResourceAsStream("my/foo.txt")).get(0));
      }
  
      public void testLoadClassOnlyInChainedClassloaders() throws Exception {
          ClassLoader cl1 = new PluginJarBuilder().
                  getClassLoader();
         ClassLoader cl2 = new PluginJarBuilder().
                 getClassLoader();
         ChainingClassLoader ccl = new ChainingClassLoader(cl1, cl2);
         assertEquals(cl1, ccl.loadClass(getClass().getName()).getClassLoader());
     }
 
     private URLClassLoader buildClassLoaderWithResources(Map<String, String> files)
             throws IOException {
         PluginJarBuilder builder = new PluginJarBuilder();
         for (Map.Entry<String, String> entry : files.entrySet()) {
             builder.addResource(entry.getKey(), entry.getValue());
         }
         return new URLClassLoader(new URL[]{builder.build().toURI().toURL()}, null);
     }
 }