OverridesJavaxInjectableMethod
This method is not annotated with @Inject, but it overrides a method that is annotated with @javax.inject.Inject. The method will not be Injected.

Severity
ERROR
Has Fix?
REQUIRES_HUMAN_ATTENTION

The problem

When classes declare that they have an @javax.inject.Injected method, dependency injection tools must call those methods after first calling any @javax.inject.Inject constructor, and performing any field injection. These methods are part of the initialization contract for the object.

When subclasses override methods annotated with @javax.inject.Inject and don’t also annotate themselves with @javax.inject.Inject, the injector will not call those methods as part of the subclass’s initialization. This may unexpectedly cause assumptions taken in the superclass (e.g.: this post-initialization routine is finished, meaning that I can safely use this field) to no longer hold.

This compile error is intended to prevent this unintentional breaking of assumptions. Possible resolutions to this error include:

Suppression

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


Positive examples

OverridesJavaxInjectableMethodPositiveCases.java

/*
* Copyright 2013 The Error Prone Authors.
*
* 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.guice.testdata;

/**
* @author sgoldfeder@gooogle.com (Steven Goldfeder)
*/

public class OverridesJavaxInjectableMethodPositiveCases {

/** Class with foo() */
public class TestClass0 {
public void foo() {}
}

/**
* Class with a method foo() that is annotated with {@code javax.inject.Inject}. Other test
* classes will extend this class.
*/

public class TestClass1 extends TestClass0 {
@javax.inject.Inject
public void foo() {}
}

/**
* Class with a method foo() that is not annotated, but overrides a method annotated with
* @javax.inject.Inject.
*/

public class TestClass2 extends TestClass1 {
// BUG: Diagnostic contains: @Inject
public void foo() {}
}

/**
* Class with a method foo() that is not annotated, but overrides a method that in turn overrides
* a method that is annotated with @javax.inject.Inject.
*/

public class TestClass3 extends TestClass2 {
// BUG: Diagnostic contains: @Inject
public void foo() {}
}
}

Negative examples

OverridesJavaxInjectableMethodNegativeCases.java

/*
* Copyright 2013 The Error Prone Authors.
*
* 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.guice.testdata;

/** @author sgoldfeder@gooogle.com (Steven Goldfeder) */
public class OverridesJavaxInjectableMethodNegativeCases {
/** Class with a method foo() with no annotations. */
public class TestClass1 {
public void foo() {}
}

/** Class with a method foo() annotated with @com.google.inject.Inject. */
public class TestClass2 {
@com.google.inject.Inject
public void foo() {}
}

/** Class with a method foo() annotated with @javax.inject.Inject. */
public class TestClass3 {
@javax.inject.Inject
public void foo() {}
}

/** OK, as it overrides a Guice-Inject method */
public class TestClass4 extends TestClass2 {
@Override
public void foo() {}
}

/** gInject <- jInject */
public class TestClass5 extends TestClass3 {
@com.google.inject.Inject
public void foo() {}
}

/** jInject <- gInject */
public class TestClass6 extends TestClass2 {
@javax.inject.Inject
public void foo() {}
}

/** OK, as 7 <- jInject <- gInject */
public class TestClass7 extends TestClass6 {
public void foo() {}
}

/** OK, as 8 <- gInject */
public class TestClass8 extends TestClass5 {
public void foo() {}
}

/** Explicitly suppressed warning */
public class TestClass9 extends TestClass3 {
@Override
@SuppressWarnings("OverridesJavaxInjectableMethod")
public void foo() {}
}
}