InjectMoreThanOneScopeAnnotationOnClass
A class can be annotated with at most one scope annotation.

Category
Severity
ERROR
Maturity

Alternate names: MoreThanOneScopeAnnotationOnClass

The problem

Annotating a class with more than one scope annotation is invalid according to the JSR-330 specification.

Suppression

Suppress false positives by adding the suppression annotation @SuppressWarnings("InjectMoreThanOneScopeAnnotationOnClass") to the enclosing element.


Positive examples

MoreThanOneScopeAnnotationOnClassPositiveCases.java

/*
* Copyright 2013 Google Inc. All Rights Reserved.
*
* 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.errorprone.bugpatterns.inject.testdata;

import com.google.inject.Singleton;
import com.google.inject.servlet.SessionScoped;
import javax.inject.Scope;

/** @author sgoldfeder@google.com(Steven Goldfeder) */
public class MoreThanOneScopeAnnotationOnClassPositiveCases {

/** Class has two scope annotations */
@Singleton
@SessionScoped
// BUG: Diagnostic contains: @Singleton(), @SessionScoped().
class TestClass1 {}

/** Class has three annotations, two of which are scope annotations. */
@Singleton
@SuppressWarnings("foo")
@SessionScoped
// BUG: Diagnostic contains: @Singleton(), @SessionScoped().
class TestClass2 {}

@Scope
@interface CustomScope {}

@Singleton
@CustomScope
@SessionScoped
// BUG: Diagnostic contains: @Singleton(), @CustomScope(), @SessionScoped().
class TestClass3 {}
}

Negative examples

MoreThanOneScopeAnnotationOnClassNegativeCases.java

/*
* Copyright 2013 Google Inc. All Rights Reserved.
*
* 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.errorprone.bugpatterns.inject.testdata;

import com.google.inject.Provides;
import com.google.inject.Singleton;
import com.google.inject.servlet.SessionScoped;
import dagger.Component;
import dagger.Subcomponent;
import dagger.producers.ProductionComponent;
import dagger.producers.ProductionSubcomponent;

/** @author sgoldfeder@google.com(Steven Goldfeder) */
public class MoreThanOneScopeAnnotationOnClassNegativeCases {

/** Class has no annotation. */
public class TestClass1 {}
/** Class has a single non scoping annotation. */
@SuppressWarnings("foo")
public class TestClass2 {}

/** Class hasa single scoping annotation. */
@Singleton
public class TestClass3 {}

/** Class has two annotations, one of which is a scoping annotation. */
@Singleton
@SuppressWarnings("foo")
public class TestClass4 {}

/**
* Class has two annotations, one of which is a scoping annotation. Class also has a method with a
* scoping annotation.
*/

@SuppressWarnings("foo")
public class TestClass5 {
@Singleton
@Provides
public void foo() {}
}

/** Class has two scoped annotations, but is a Dagger component */
@Singleton
@SessionScoped
@Component
public class DaggerComponent {}

/** Class has two scoped annotations, but is a Dagger subcomponent */
@Singleton
@SessionScoped
@Subcomponent
public class DaggerSubcomponent {}

/** Class has two scoped annotations, but is a Dagger component */
@Singleton
@SessionScoped
@ProductionComponent
public class DaggerProductionComponent {}

/** Class has two scoped annotations, but is a Dagger subcomponent */
@Singleton
@SessionScoped
@ProductionSubcomponent
public class DaggerProductionSubcomponent {}

/** Suppression through secondary name */
@SuppressWarnings("MoreThanOneScopeAnnotationOnClass")
public class TestClass6 {}
}