我已阅读https://github.com/google/guice/wiki/AssistedInject,但它没有说明如何传递AssistedInject参数的值.injector.getInstance()调用会是什么样的？
从Play Framework 2.4开始,就有可能使用依赖注入(使用Guice).
AuthenticationService在我的ActionBuilders中使用对象之前(例如):
object AuthenticatedAction extends ActionBuilder[AuthenticatedRequest] {
override def invokeBlock[A](request: Request[A], block: (AuthenticatedRequest[A]) => Future[Result]): Future[Result] = {
...
AuthenticationService.authenticate (...)
...
}
}
现在AuthenticationService不再是一个对象,而是一个类.我怎么还能使用AuthenticationService我的ActionBuilder？
到目前为止,我成功地使用了google guice 2.在迁移到guice 3.0时,我遇到了辅助注入工厂的麻烦.假设以下代码
public interface Currency {}
public class SwissFrancs implements Currency {}
public interface Payment<T extends Currency> {}
public class RealPayment implements Payment<SwissFrancs> {
@Inject
RealPayment(@Assisted Date date) {}
}
public interface PaymentFactory {
Payment<Currency> create(Date date);
}
public SwissFrancPaymentModule extends AbstractModule {
protected void configure() {
install(new FactoryModuleBuilder()
.implement(Payment.class, RealPayment.class)
.build(PaymentFactory.class));
}
}
在创建注入器时,我得到以下异常:
com.google.inject.CreationException: Guice creation errors:
1) Payment<Currency> is an interface, not a concrete class.
Unable to create AssistedInject factory. while locating Payment<Currency>
at PaymentFactory.create(PaymentFactory.java:1) …我正在学习Guice,我不清楚如何使用Injector实例.最好Injector在应用程序引导程序上创建一次实例,并使其成为公共单例？
我们总是必须使用Injector#getInstance(SomeClass.class)我们推出Guice @Inject注释的课程,这是真的吗？
我对guice注射有疑问.是否可以将@named变量值注入静态变量？
我试过了
@Provides
@Named("emp.id")
public Integer getEmpId() {
return 2;
}
并试图将此值注入静态变量,如
@Inject
@Named("emp.id")
private static Integer id;
但id返回值为null,当我删除静态修饰符时,id给出了值1.
这里到底发生了什么？
我正在尝试将Google Guice集成到AWS Lambda中,但由于某些原因,注入效果不佳.每当我试着打电话时,它都会给我null
处理程序代码:
public class FirstLamdba implements RequestHandler<Request, Object>{
private UserService userService;
@Inject
public void seUserService(UserService userService) {
this.userService = userService;
}
public Object handleRequest(Request request, Context context){
userService.persistData();
}
UserService
public interface UserService {
List<String> persistData();
}
UserServiceImpl
public class UserServiceImpl implements UserService{
@Override
public List<String> persistData() {
System.out.println("***Working*********");
}
绑定类:
public class MessageGuiceModule extends AbstractModule
{
protected void configure() {
bind(UserService.class).to(UserServiceImpl.class);
}
}
测试类:
@Test
public void testLambdaFunctionHandler() {
Request request = new Request();
request.setName("Name");
FirstLamdba handler …为什么Guice 3.0针对错误的配置组件（例如，缺少@Inject）抛出此异常而不是格式化消息？
Exception in thread "main" com.google.inject.internal.util.$ComputationException: java.lang.ArrayIndexOutOfBoundsException: 16640
at com.google.inject.internal.util.$MapMaker$StrategyImpl.compute(MapMaker.java:553)
at com.google.inject.internal.util.$MapMaker$StrategyImpl.compute(MapMaker.java:419)
at com.google.inject.internal.util.$CustomConcurrentHashMap$ComputingImpl.get(CustomConcurrentHashMap.java:2041)
at com.google.inject.internal.util.$StackTraceElements.forMember(StackTraceElements.java:53)
at com.google.inject.internal.Errors.formatInjectionPoint(Errors.java:716)
at com.google.inject.internal.Errors.formatSource(Errors.java:678)
at com.google.inject.internal.Errors.format(Errors.java:555)
at com.google.inject.ConfigurationException.getMessage(ConfigurationException.java:70)
at java.lang.Throwable.getLocalizedMessage(Throwable.java:391)
at java.lang.Throwable.toString(Throwable.java:480)
at java.lang.String.valueOf(String.java:2982)
at java.io.PrintStream.println(PrintStream.java:821)
at java.lang.Throwable$WrappedPrintStream.println(Throwable.java:748)
at java.lang.Throwable.printStackTrace(Throwable.java:655)
at java.lang.Throwable.printStackTrace(Throwable.java:643)
at java.lang.Throwable.printStackTrace(Throwable.java:634)
at hu.daniel.hari.exercises.cleanarchitecture.payrollcasestudy.adapters.primary.ui.impl.swing._2.SwingUIMain2.<init>(SwingUIMain2.java:40)
at hu.daniel.hari.exercises.cleanarchitecture.payrollcasestudy.adapters.primary.ui.impl.swing._2.SwingUIMain2.main(SwingUIMain2.java:17)
Caused by: java.lang.ArrayIndexOutOfBoundsException: 16640
at com.google.inject.internal.asm.$ClassReader.readClass(Unknown Source)
at com.google.inject.internal.asm.$ClassReader.accept(Unknown Source)
at com.google.inject.internal.asm.$ClassReader.accept(Unknown Source)
at com.google.inject.internal.util.$LineNumbers.<init>(LineNumbers.java:62)
at com.google.inject.internal.util.$StackTraceElements$1.apply(StackTraceElements.java:36)
at com.google.inject.internal.util.$StackTraceElements$1.apply(StackTraceElements.java:33)
at com.google.inject.internal.util.$MapMaker$StrategyImpl.compute(MapMaker.java:549)
... 17 more
我initating代码是：
Injector injector = Guice.createInjector(new SwingUIModule(useCaseFactory));
injector.getInstance(MainFrameUI.class).show();
我遇到以下问题,我尝试启动jetty,我得到以下的例外:
Execution default-test of goal org.apache.maven.plugins:maven-surefire-plugin:2.17:test failed: There was an error in the forked process
[ERROR] org.apache.maven.surefire.testset.TestSetFailedException: java.lang.RuntimeException: com.google.inject.internal.util.$ComputationException: java.lang.ArrayIndexOutOfBoundsException: 51966
[ERROR] at org.apache.maven.surefire.common.junit4.JUnit4RunListener.rethrowAnyTestMechanismFailures(JUnit4RunListener.java:206)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.createRequestAndRun(JUnitCoreWrapper.java:114)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.executeEager(JUnitCoreWrapper.java:85)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.execute(JUnitCoreWrapper.java:54)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreProvider.invoke(JUnitCoreProvider.java:134)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.invokeProviderInSameClassLoader(ForkedBooter.java:200)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.runSuitesInProcess(ForkedBooter.java:153)
[ERROR] at org.apache.maven.surefire.booter.ForkedBooter.main(ForkedBooter.java:103)
[ERROR] Caused by: java.lang.RuntimeException: com.google.inject.internal.util.$ComputationException: java.lang.ArrayIndexOutOfBoundsException: 51966
[ERROR] at org.apache.maven.surefire.junitcore.TestSet.replay(TestSet.java:100)
[ERROR] at org.apache.maven.surefire.junitcore.ConcurrentRunListener.testSetCompleted(ConcurrentRunListener.java:82)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreRunListener.testRunFinished(JUnitCoreRunListener.java:73)
[ERROR] at org.junit.runner.notification.RunNotifier$2.notifyListener(RunNotifier.java:95)
[ERROR] at org.junit.runner.notification.RunNotifier$SafeNotifier.run(RunNotifier.java:61)
[ERROR] at org.junit.runner.notification.RunNotifier.fireTestRunFinished(RunNotifier.java:92)
[ERROR] at org.junit.runner.JUnitCore.run(JUnitCore.java:161)
[ERROR] at org.junit.runner.JUnitCore.run(JUnitCore.java:138)
[ERROR] at org.apache.maven.surefire.junitcore.JUnitCoreWrapper.createRequestAndRun(JUnitCoreWrapper.java:113)
[ERROR] …是否有任何光滑的方式(如果有的话)Guice以某种方式将类类型绑定到接口？我不是指类的实例,而是实际的java.lang.class类型本身.
即(显然不起作用,但告诉我我追求的是什么):
bind(MyInterface.class).to(Class<MyImplementation>)
我知道一开始似乎不可能,但我不知道是否有任何技巧可以用来做到这一点.想到的是将类类型包装在实际的实例化对象或其他东西中,但这似乎是最后的手段.
任何想法将不胜感激.谢谢!
guice 4.0向后兼容3.x吗？无法从发行说明或常见问题解答中找到它...
如果没有,是否有某个兼容性问题列表？
这有效：
public static class SomeGenericType<T> {
private TypeLiteral<T> type;
@Inject
public SomeGenericType(TypeLiteral<T> type) {
this.type = type;
}
public Class<? super T> getType() {
return type.getRawType();
}
}
当我这样做时，Guice自动注入表示字符串的TypeLiteral：
@Inject SomeGenericType<String> foo;
但是在使用Assisted Inject尝试相同的操作时：
public static interface FooFactory<T> {
Foo<T> create(String name);
}
public static class Foo<T> {
@AssistedInject
public Foo(TypeLiteral<T> type, @Assisted String name) {
....
我的模块如下所示：
public static class TestMod extends AbstractModule {
@Override
protected void configure() {
install(new FactoryModuleBuilder().build(new TypeLiteral<FooFactory<String>>(){}));
}
}
安装模块时出现异常：
TypeLiteral<T> cannot be used …