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Android Dagger 2 Generated annotation JSR250

When you’re using Dagger 2.0 in your Android projects, you’ll quickly realize you need to include an additional dependency to provide the @Generated annotation (from JSR-250). [**]

These are the common options typically seen in online Dagger examples:

  1. javax.annotation:jsr250-api:1.0
  2. org.glassfish:javax.annotation:10.0-b28
  3. javax.annotation:javax.annotation-api:1.2

So which one should you use?

Let’s do a quick comparison of the 3 jars:

  1. javax.annotation:jsr250-api:1.0

    • Jar file size: 5.7kb
    • Date of javax directory: Apr 27, 2006
    • License:
    • Created-By: 1.5.0_05-b05 (Sun Microsystems Inc.)
  2. org.glassfish:javax.annotation:10.0-b28

    • Jar file size: 20kb
    • Date of javax directory: Oct 8, 2008
    • License:
    • Created-By: Apache Maven Bundle Plugin
  3. javax.annotation:javax.annotation-api:1.2

    • Jar file size: 26kb
    • Date of javax directory: Apr 26, 2013
    • Created-By: Created-By: 1.7.0_09 (Oracle Corporation)
    • License:

So the second contains slightly more meta-data files and a different license (includes GPL) than the first option, but otherwise they contain essentially the same content - e.g. the same .class files.

The third one contains a few extra annotations, including: @ManagedBean, @Priority, but is pretty much the same as the second one.

Verdict: use the first/oldest one: javax.annotation:jsr250-api:1.0

Final note: when you include the dependency in your android project, use the provided scope instead of compile, to prevent the JSR-250 annotations from being distributed with your app, in other words:

dependencies {
    compile ''
    provided 'javax.annotation:jsr250-api:1.0'
    apt ''

** PS. if you don’t include one of these JSR-250 jars in your project, you’ll get this compile error in one of the files generated by dagger-compiler:

Error:(17, 24) error: package javax.annotation does not exist
Error:(20, 2) error: cannot find symbol class Generated
Error:(21, 14) error: dagger.internal.codegen.ComponentProcessor was unable to process this class because not all of its dependencies could be resolved. Check for compilation errors or a circular dependency with generated code.