Java example source code file (RequestInjectionTest.java)

This example Java source code file (RequestInjectionTest.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.

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Java - Java tags/keywords

abstractmodule, annotation, creationexception, error, forfield, hasinjections, inject, needsrunnable, object, override, pop, retention, snap, string, unsupportedoperationexception

The RequestInjectionTest.java Java example source code

/**
 * Copyright (C) 2006 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;

import static com.google.inject.Asserts.assertContains;
import static com.google.inject.Asserts.getDeclaringSourcePart;
import static java.lang.annotation.RetentionPolicy.RUNTIME;

import com.google.inject.matcher.Matchers;
import com.google.inject.spi.TypeEncounter;
import com.google.inject.spi.TypeListener;

import junit.framework.TestCase;

import java.lang.annotation.Retention;

/**
 * @author crazybob@google.com (Bob Lee)
 */
public class RequestInjectionTest extends TestCase {

  @Retention(RUNTIME)
  @BindingAnnotation @interface ForField {}

  @Retention(RUNTIME)
  @BindingAnnotation @interface ForMethod {}

  @Override
  protected void setUp() throws Exception {
    super.setUp();
    HasInjections.staticField = 0;
    HasInjections.staticMethod = null;
  }

  public void testInjectMembers() {
    final HasInjections hi = new HasInjections();

    Guice.createInjector(new AbstractModule() {
      @Override
      protected void configure() {
        bindConstant().annotatedWith(ForMethod.class).to("test");
        bindConstant().annotatedWith(ForField.class).to(5);
        requestInjection(hi);
      }
    });

    assertEquals("test", hi.instanceMethod);
    assertEquals(5, hi.instanceField);
    assertNull(HasInjections.staticMethod);
    assertEquals(0, HasInjections.staticField);
  }

  public void testInjectStatics() throws CreationException {
    Guice.createInjector(new AbstractModule() {
      @Override
      protected void configure() {
        bindConstant().annotatedWith(ForMethod.class).to("test");
        bindConstant().annotatedWith(ForField.class).to(5);
        requestStaticInjection(HasInjections.class);
      }
    });

    assertEquals("test", HasInjections.staticMethod);
    assertEquals(5, HasInjections.staticField);
  }
  
  public void testInjectMembersAndStatics() {
    final HasInjections hi = new HasInjections();

    Guice.createInjector(new AbstractModule() {
      @Override
      protected void configure() {
        bindConstant().annotatedWith(ForMethod.class).to("test");
        bindConstant().annotatedWith(ForField.class).to(5);
        requestStaticInjection(HasInjections.class);
        requestInjection(hi);
      }
    });

    assertEquals("test", hi.instanceMethod);
    assertEquals(5, hi.instanceField);
    assertEquals("test", HasInjections.staticMethod);
    assertEquals(5, HasInjections.staticField);
  }

  public void testValidationErrorOnInjectedMembers() {
    try {
      Guice.createInjector(new AbstractModule() {
        @Override
        protected void configure() {
          requestInjection(new NeedsRunnable());
        }
      });
    } catch (CreationException expected) {
      assertContains(expected.getMessage(),
          "1) No implementation for java.lang.Runnable was bound",
          "at " + NeedsRunnable.class.getName(), ".runnable(RequestInjectionTest.java:");
    }
  }

  public void testInjectionErrorOnInjectedMembers() {
    try {
      Guice.createInjector(new AbstractModule() {
        @Override
        protected void configure() {
          bind(Runnable.class).toProvider(new Provider<Runnable>() {
            public Runnable get() {
              throw new UnsupportedOperationException();
            }
          });
          requestInjection(new NeedsRunnable());
        }
      });
    } catch (CreationException expected) {
      assertContains(expected.getMessage(),
          "1) Error in custom provider, java.lang.UnsupportedOperationException",
          "for field at " + NeedsRunnable.class.getName() + ".runnable(RequestInjectionTest.java:",
          "at " + getClass().getName(), getDeclaringSourcePart(getClass()));
    }
  }

  public void testUserExceptionWhileInjectingInstance() {
    try {
      Guice.createInjector(new AbstractModule() {
        @Override
        protected void configure() {
          requestInjection(new BlowsUpOnInject());
        }
      });
      fail();
    } catch (CreationException expected) {
      assertContains(expected.getMessage(),
          "1) Error injecting method, java.lang.UnsupportedOperationException: Pop",
          "at " + BlowsUpOnInject.class.getName() + ".injectInstance(RequestInjectionTest.java:");
    }
  }

  public void testUserExceptionWhileInjectingStatically() {
    try {
      Guice.createInjector(new AbstractModule() {
        @Override
        protected void configure() {
          requestStaticInjection(BlowsUpOnInject.class);
        }
      });
      fail();
    } catch (CreationException expected) {
      assertContains(expected.getMessage(),
          "1) Error injecting method, java.lang.UnsupportedOperationException: Snap",
          "at " + BlowsUpOnInject.class.getName() + ".injectStatically(RequestInjectionTest.java:");
    }
  }

  static class NeedsRunnable {
    @Inject Runnable runnable;
  }

  static class HasInjections {

    @Inject @ForField static int staticField;
    @Inject @ForField int instanceField;

    static String staticMethod;
    String instanceMethod;

    @Inject static void setStaticMethod(@ForMethod String staticMethod) {
      HasInjections.staticMethod = staticMethod;
    }

    @Inject void setInstanceS(@ForMethod String instanceS) {
      this.instanceMethod = instanceS;
    }
  }

  static class BlowsUpOnInject {
    @Inject void injectInstance() {
      throw new UnsupportedOperationException("Pop");
    }

    @Inject static void injectStatically() {
      throw new UnsupportedOperationException("Snap");
    }
  }
  
  /*
   * Tests that initializables of the same instance don't clobber
   * membersInjectors in InitializableReference, so that they ultimately
   * can be requested in any order.
   */
  public void testEarlyInjectableReferencesWithSameIdentity() {
    Injector injector = Guice.createInjector(new AbstractModule() {
      @Override
      protected void configure() {
        // Add a listener to trigger all toInstance bindings to get an Initializable.
        bindListener(Matchers.any(), new TypeListener() {
          @Override
          public <I> void hear(TypeLiteral type, TypeEncounter encounter) {
          }
        });
        
        // Bind two different Keys to the IDENTITICAL object
        // ORDER MATTERS! We want the String binding to push out the Object one
        String fail = new String("better not fail!");
        bind(Object.class).toInstance(fail);
        bind(String.class).toInstance(fail);
        
        // Then try to inject those objects in a requestInjection,
        // letting us get into InjectableReference.get before it has
        // finished running through all its injections.
        // Each of these technically has its own InjectableReference internally.
        // ORDER MATTERS!.. because Object is injected first, that InjectableReference
        // attempts to process its members injector, but it wasn't initialized,
        // because String pushed it out of the queue!
        requestInjection(new Object() {
          @SuppressWarnings("unused") @Inject Object obj;
          @SuppressWarnings("unused") @Inject String str;
        });
      }
    });
  }
}