home | career | drupal | java | mac | mysql | perl | scala | uml | unix  

Java example source code file (ModuleAnnotatedMethodScannerTest.java)

This example Java source code file (ModuleAnnotatedMethodScannerTest.java) is included in the alvinalexander.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" TM.

Learn more about this Java project at its project page.

Java - Java tags/keywords

abstractmodule, annotation, binding, class, exception, exposed, injector, key, named, namedmunger, override, privatemodule, string, target, testprovides, util

The ModuleAnnotatedMethodScannerTest.java Java example source code

/**
 * Copyright (C) 2015 Google Inc.
 *
 * 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.
 */

package com.google.inject.spi;

import static com.google.inject.Asserts.assertContains;
import static com.google.inject.name.Names.named;
import static java.lang.annotation.ElementType.METHOD;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.google.common.collect.ImmutableSet;
import com.google.common.collect.Iterables;
import com.google.inject.AbstractModule;
import com.google.inject.Binder;
import com.google.inject.Binding;
import com.google.inject.CreationException;
import com.google.inject.Exposed;
import com.google.inject.Guice;
import com.google.inject.Injector;
import com.google.inject.Key;
import com.google.inject.Module;
import com.google.inject.PrivateModule;
import com.google.inject.internal.util.StackTraceElements;
import com.google.inject.name.Named;
import com.google.inject.name.Names;

import junit.framework.TestCase;

import java.lang.annotation.Annotation;
import java.lang.annotation.Documented;
import java.lang.annotation.Retention;
import java.lang.annotation.Target;
import java.util.Set;

/** Tests for {@link ModuleAnnotatedMethodScanner} usage. */
public class ModuleAnnotatedMethodScannerTest extends TestCase {

  public void testScanning() throws Exception {
    Module module = new AbstractModule() {
      @Override protected void configure() {}

      @TestProvides @Named("foo") String foo() {
        return "foo";
      }

      @TestProvides @Named("foo2") String foo2() {
        return "foo2";
      }
    };
    Injector injector = Guice.createInjector(module, NamedMunger.module());

    // assert no bindings named "foo" or "foo2" exist -- they were munged.
    assertMungedBinding(injector, String.class, "foo", "foo");
    assertMungedBinding(injector, String.class, "foo2", "foo2");

    Binding<String> fooBinding = injector.getBinding(Key.get(String.class, named("foo-munged")));
    Binding<String> foo2Binding = injector.getBinding(Key.get(String.class, named("foo2-munged")));
    // Validate the provider has a sane toString
    assertEquals(methodName(TestProvides.class, "foo", module),
        fooBinding.getProvider().toString());
    assertEquals(methodName(TestProvides.class, "foo2", module),
        foo2Binding.getProvider().toString());
  }

  public void testSkipSources() throws Exception {
    Module module = new AbstractModule() {
      @Override protected void configure() {
        binder().skipSources(getClass()).install(new AbstractModule() {
          @Override protected void configure() {}

          @TestProvides @Named("foo") String foo() { return "foo"; }
        });
      }
    };
    Injector injector = Guice.createInjector(module, NamedMunger.module());
    assertMungedBinding(injector, String.class, "foo", "foo");
  }
  
  public void testWithSource() throws Exception {
    Module module = new AbstractModule() {
      @Override protected void configure() {
        binder().withSource("source").install(new AbstractModule() {
          @Override protected void configure() {}

          @TestProvides @Named("foo") String foo() { return "foo"; }
        });
      }
    };
    Injector injector = Guice.createInjector(module, NamedMunger.module());
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testMoreThanOneClaimedAnnotationFails() throws Exception {
    Module module = new AbstractModule() {
      @Override protected void configure() {}

      @TestProvides @TestProvides2 String foo() {
        return "foo";
      }
    };
    try {
      Guice.createInjector(module, NamedMunger.module());
      fail();
    } catch(CreationException expected) {
      assertEquals(1, expected.getErrorMessages().size());
      assertContains(expected.getMessage(),
          "More than one annotation claimed by NamedMunger on method "
              + module.getClass().getName() + ".foo(). Methods can only have "
              + "one annotation claimed per scanner.");
    }
  }

  private String methodName(Class<? extends Annotation> annotation, String method, Object container)
      throws Exception {
    return "@" + annotation.getName() + " "
        + StackTraceElements.forMember(container.getClass().getDeclaredMethod(method));
  }

  @Documented @Target(METHOD) @Retention(RUNTIME)
  private @interface TestProvides {}

  @Documented @Target(METHOD) @Retention(RUNTIME)
  private @interface TestProvides2 {}

  private static class NamedMunger extends ModuleAnnotatedMethodScanner {
    static Module module() {
      return new AbstractModule() {
        @Override protected void configure() {
          binder().scanModulesForAnnotatedMethods(new NamedMunger());
        }
      };
    }

    @Override
    public String toString() {
      return "NamedMunger";
    }

    @Override
    public Set<? extends Class annotationClasses() {
      return ImmutableSet.of(TestProvides.class, TestProvides2.class);
    }

    @Override
    public <T> Key prepareMethod(Binder binder, Annotation annotation, Key key,
        InjectionPoint injectionPoint) {
      return Key.get(key.getTypeLiteral(),
          Names.named(((Named) key.getAnnotation()).value() + "-munged"));
    }
  }

  private void assertMungedBinding(Injector injector, Class<?> clazz, String originalName,
      Object expectedValue) {
    assertNull(injector.getExistingBinding(Key.get(clazz, named(originalName))));
    Binding<?> fooBinding = injector.getBinding(Key.get(clazz, named(originalName + "-munged")));
    assertEquals(expectedValue, fooBinding.getProvider().get());
  }

  public void testFailingScanner() {
    try {
      Guice.createInjector(new SomeModule(), FailingScanner.module());
      fail();
    } catch (CreationException expected) {
      Message m = Iterables.getOnlyElement(expected.getErrorMessages());
      assertEquals(
          "An exception was caught and reported. Message: Failing in the scanner.",
          m.getMessage());
      assertEquals(IllegalStateException.class, m.getCause().getClass());
      ElementSource source = (ElementSource) Iterables.getOnlyElement(m.getSources());
      assertEquals(SomeModule.class.getName(),
          Iterables.getOnlyElement(source.getModuleClassNames()));
      assertEquals(String.class.getName() + " " + SomeModule.class.getName() + ".aString()",
          source.toString());
    }
  }

  public static class FailingScanner extends ModuleAnnotatedMethodScanner {
    static Module module() {
      return new AbstractModule() {
        @Override protected void configure() {
          binder().scanModulesForAnnotatedMethods(new FailingScanner());
        }
      };
    }

    @Override public Set<? extends Class annotationClasses() {
      return ImmutableSet.of(TestProvides.class);
    }

    @Override public <T> Key prepareMethod(
        Binder binder, Annotation rawAnnotation, Key<T> key, InjectionPoint injectionPoint) {
      throw new IllegalStateException("Failing in the scanner.");
    }
  }

  static class SomeModule extends AbstractModule {
    @TestProvides String aString() {
      return "Foo";
    }

    @Override protected void configure() {}
  }

  public void testChildInjectorInheritsScanner() {
    Injector parent = Guice.createInjector(NamedMunger.module());
    Injector child = parent.createChildInjector(new AbstractModule() {
      @Override protected void configure() {}

      @TestProvides @Named("foo") String foo() {
        return "foo";
      }
    });
    assertMungedBinding(child, String.class, "foo", "foo");
  }

  public void testChildInjectorScannersDontImpactSiblings() {
    Module module = new AbstractModule() {
      @Override
      protected void configure() {}

      @TestProvides @Named("foo") String foo() {
        return "foo";
      }
    };
    Injector parent = Guice.createInjector();
    Injector child = parent.createChildInjector(NamedMunger.module(), module);
    assertMungedBinding(child, String.class, "foo", "foo");

    // no foo nor foo-munged in sibling, since scanner never saw it.
    Injector sibling = parent.createChildInjector(module);
    assertNull(sibling.getExistingBinding(Key.get(String.class, named("foo"))));
    assertNull(sibling.getExistingBinding(Key.get(String.class, named("foo-munged"))));
  }

  public void testPrivateModuleInheritScanner_usingPrivateModule() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new PrivateModule() {
      @Override protected void configure() {}

      @Exposed @TestProvides @Named("foo") String foo() {
        return "foo";
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModule_skipSourcesWithinPrivateModule() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new PrivateModule() {
      @Override protected void configure() {
        binder().skipSources(getClass()).install(new AbstractModule() {
          @Override protected void configure() {}
          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModule_skipSourcesForPrivateModule() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new AbstractModule() {
      @Override protected void configure() {
        binder().skipSources(getClass()).install(new PrivateModule() {
          @Override protected void configure() {}

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }});
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleInheritScanner_usingPrivateBinder() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new AbstractModule() {
      @Override protected void configure() {
        binder().newPrivateBinder().install(new AbstractModule() {
          @Override protected void configure() {}

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleInheritScanner_skipSourcesFromPrivateBinder() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new AbstractModule() {
      @Override protected void configure() {
        binder().newPrivateBinder().skipSources(getClass()).install(new AbstractModule() {
          @Override protected void configure() {}

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleInheritScanner_skipSourcesFromPrivateBinder2() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new AbstractModule() {
      @Override protected void configure() {
        binder().skipSources(getClass()).newPrivateBinder().install(new AbstractModule() {
          @Override protected void configure() {}

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleScannersDontImpactSiblings_usingPrivateModule() {
    Injector injector = Guice.createInjector(new PrivateModule() {
      @Override protected void configure() {
        install(NamedMunger.module());
      }

      @Exposed @TestProvides @Named("foo") String foo() {
        return "foo";
      }
    }, new PrivateModule() {
      @Override protected void configure() {}

      // ignored! (because the scanner doesn't run over this module)
      @Exposed @TestProvides @Named("foo") String foo() {
        return "foo";
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleScannersDontImpactSiblings_usingPrivateBinder() {
    Injector injector = Guice.createInjector(new AbstractModule() {
      @Override protected void configure() {
        binder().newPrivateBinder().install(new AbstractModule() {
          @Override protected void configure() {
            install(NamedMunger.module());
          }

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    }, new AbstractModule() {
      @Override protected void configure() {
        binder().newPrivateBinder().install(new AbstractModule() {
          @Override protected void configure() {}

          // ignored! (because the scanner doesn't run over this module)
          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }});
    assertMungedBinding(injector, String.class, "foo", "foo");
  }

  public void testPrivateModuleWithinPrivateModule() {
    Injector injector = Guice.createInjector(NamedMunger.module(), new PrivateModule() {
      @Override protected void configure() {
        expose(Key.get(String.class, named("foo-munged")));
        install(new PrivateModule() {
          @Override protected void configure() {}

          @Exposed @TestProvides @Named("foo") String foo() {
            return "foo";
          }
        });
      }
    });
    assertMungedBinding(injector, String.class, "foo", "foo");
  }
}

Other Java examples (source code examples)

Here is a short list of links related to this Java ModuleAnnotatedMethodScannerTest.java source code file:



my book on functional programming

 

new blog posts

 

Copyright 1998-2021 Alvin Alexander, alvinalexander.com
All Rights Reserved.

A percentage of advertising revenue from
pages under the /java/jwarehouse URI on this website is
paid back to open source projects.