Produced source JARs don't correspond to files in class JAR

[vmax]

Description of the problem / feature request:

Source JARs produced currently replicate the structure of source files used to build the class JAR. Example:

ghost:c vmax$ bazel build //:libanotherlib-src.jar
…
Target //:libanotherlib-src.jar up-to-date:
  bazel-bin/libanotherlib-src.jar

ghost:c vmax$ jar tf bazel-bin/libanotherlib-src.jar
META-INF/
META-INF/MANIFEST.MF
Anotherlib.java

Given this example, I would expect source JAR to contain structure similar to the following:

META-INF/
META-INF/MANIFEST.MF
com/
com/smth/
com/smth/Anotherlib.java

Feature requests: what underlying problem are you trying to solve with this feature?

We need produced source JARs to have the same structure as class files inside class JAR so that:

• produced source JARs could be deployed to Maven Central
• "Go to source" functionality works with IntelliJ IDEA + Bazel plugin

Bugs: what's the simplest, easiest way to reproduce this bug? Please provide a minimal example if possible.

ghost:c vmax$ cat BUILD 
java_library(
    name = "anotherlib",
    srcs = ["Anotherlib.java"],
    visibility = ["//visibility:public"]
)

ghost:c vmax$ cat AnotherLib.java 
package com.smth;

public class Anotherlib {
    public Anotherlib() {
        System.err.println("ctor");
    }
}

What operating system are you running Bazel on?

macOS Mojave 10.14.4

What's the output of bazel info release?

release 0.25.0

Have you found anything relevant by searching the web?

—

[davido]

Create java/com/smth directory, move there your Anotherlib.java and change your BUILD file like this:

java_library(
    name = "anotherlib",
    srcs = ["java/com/smth/Anotherlib.java"],
    visibility = ["//visibility:public"]
)

Check Gerrit Code Review: [1]. We do it like I described above and we put JARs and source-JARs created by Bazel to Maven Central:

  $ bazel build java/com/google/gerrit/common:server

and check the structure of the resulted JAR an source-JAR.

[1] https://github.com/GerritCodeReview/gerrit/blob/master/java/com/google/gerrit/common/BUILD

[vmax]

@davido thank you for your suggestion! however, my intention is to preserve the directory structure we currently have where directories represent logical separation of modules and not necessarily java packaging

[vmax]

We were able to resolve it by wrapping singlejar in a Java wrapper (src) and using custom java_toolchain (src)

[vmax]

We've addressed it by using a workaround on plugin level: bazelbuild/intellij#1206, bazelbuild/intellij#1207

[davido]

@vmax Can you re-open this issue? Alternatively, I can open a new issue for source path normalization in created "-src.jar" in java_library rule.

I am facing a similar problem, when trying to migrate existing project to Bazel an I think, that this should be fixed in Bazel.

Consider this directory structure (that I cannot change):

<workspace_root>/foo/org/example/app/Test.java

The build file is put in foo directory. The java_library rule is:

java_library(
  name = "foo",
  srcs = glob(["org/**/*.java"]),
)

When building foo the java library is correct, but the libfoo-src.jar is wrong: it has this entry:

"foo/org/example/app/Test.java"
instead
"org/example/app/Test.java"

Note, that if I rename the foo directory to one of these directories:

• java
• src
• src/main/java

then the "foo" directory is stripped. One approach to fix that would be to provide source_strip_prefix in java_library rule or apply resource_strip_prefix on path normalization in "-src.jar" file.

One workaround, that can be done now, is to create srcjar manually and provide it as source to the java_library rule. Using java_binary, the sources can be provided as resources and the path can be normalized using resource_strip_prefix=foo, so something like:

# TODO(davido): Remove that hack to create source package without the wrong path prefix.
java_binary(
    name = "foo-src-binary",
    main_class = "Dummy.java",
    resources = glob(["org/**/*.java"]),
    resource_strip_prefix = "foo",
)

# TODO(davido): Remove that hack to rename the java_binary source with ".jar" suffix
# to zip file with ".srcjar" suffix so that java_library can accept it.
genrule2(
    name = "foo-src",
    cmd = "mv $< $@",
    srcs = [":foo-src-binary_deploy.jar"],
    outs = ["foo.srcjar"],
)

java_library(
    name = "foo",
    srcs = [":foo-src"],
)

[vmax]

@davido I think you should open another one: you might have another reasons for wanting to have a correct source JAR and will then be able to convince Bazel team to look at them 🙂