Default java toolchain target

The previous javac version used by the default_java_toolchain in Bazel had a non-standard modification to default to the Java 8 language level, which wasn't carried forward to 11. Adding default values for {source,target}_version in the default_java_toolchain to keep Bazel backwards compatibility.

Fixes #8539.

Closes #8569.

PiperOrigin-RevId: 251848351

.bazelci/postsubmit.yml

@@ -124,6 +124,7 @@ platforms:
       - "-//src/test/shell/bazel:bazel_determinism_test"
       - "-//src/test/shell/bazel:bazel_example_test"
       - "-//src/test/shell/bazel:bazel_java_test"
+      - "-//src/test/shell/bazel:bazel_java_test_defaults"
       - "-//src/test/shell/bazel:bazel_random_characters_test"
       - "-//src/test/shell/bazel:bazel_repository_cache_test"
       - "-//src/test/shell/bazel:bazel_rules_test"
@@ -193,6 +194,7 @@ platforms:
       - "-//src/test/shell/bazel:bazel_determinism_test"
       - "-//src/test/shell/bazel:bazel_example_test"
       - "-//src/test/shell/bazel:bazel_java_test"
+      - "-//src/test/shell/bazel:bazel_java_test_defaults"
       - "-//src/test/shell/bazel:bazel_random_characters_test"
       - "-//src/test/shell/bazel:bazel_repository_cache_test"
       - "-//src/test/shell/bazel:bazel_rules_test"

.bazelci/presubmit.yml

@@ -125,6 +125,7 @@ platforms:
       - "-//src/test/shell/bazel:bazel_determinism_test"
       - "-//src/test/shell/bazel:bazel_example_test"
       - "-//src/test/shell/bazel:bazel_java_test"
+      - "-//src/test/shell/bazel:bazel_java_test_defaults"
       - "-//src/test/shell/bazel:bazel_random_characters_test"
       - "-//src/test/shell/bazel:bazel_repository_cache_test"
       - "-//src/test/shell/bazel:bazel_rules_test"
@@ -191,6 +192,7 @@ platforms:
       - "-//src/test/shell/bazel:bazel_determinism_test"
       - "-//src/test/shell/bazel:bazel_example_test"
       - "-//src/test/shell/bazel:bazel_java_test"
+      - "-//src/test/shell/bazel:bazel_java_test_defaults"
       - "-//src/test/shell/bazel:bazel_random_characters_test"
       - "-//src/test/shell/bazel:bazel_repository_cache_test"
       - "-//src/test/shell/bazel:bazel_rules_test"

src/test/shell/bazel/BUILD

@@ -146,6 +146,15 @@ sh_test(
     ],
 )
 
+sh_test(
+    name = "bazel_java_test_defaults",
+    srcs = ["bazel_java_test_defaults.sh"],
+    data = [
+        ":test-deps",
+        "@bazel_tools//tools/bash/runfiles",
+    ],
+)
+
 sh_test(
     name = "bazel_java_test",
     # TODO(iirina): Investigate if the 'large' and 'eternal' values still apply.

src/test/shell/bazel/bazel_java_test_defaults.sh

@@ -0,0 +1,92 @@
+#!/bin/bash
+#
+# Copyright 2016 The Bazel Authors. 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.
+#
+# Tests the java rules with the default values provided by Bazel.
+#
+
+add_to_bazelrc "build --javabase=@bazel_tools//tools/jdk:remote_jdk11"
+
+# --- begin runfiles.bash initialization ---
+if [[ ! -d "${RUNFILES_DIR:-/dev/null}" && ! -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+    if [[ -f "$0.runfiles_manifest" ]]; then
+      export RUNFILES_MANIFEST_FILE="$0.runfiles_manifest"
+    elif [[ -f "$0.runfiles/MANIFEST" ]]; then
+      export RUNFILES_MANIFEST_FILE="$0.runfiles/MANIFEST"
+    elif [[ -f "$0.runfiles/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+      export RUNFILES_DIR="$0.runfiles"
+    fi
+fi
+if [[ -f "${RUNFILES_DIR:-/dev/null}/bazel_tools/tools/bash/runfiles/runfiles.bash" ]]; then
+  source "${RUNFILES_DIR}/bazel_tools/tools/bash/runfiles/runfiles.bash"
+elif [[ -f "${RUNFILES_MANIFEST_FILE:-/dev/null}" ]]; then
+  source "$(grep -m1 "^bazel_tools/tools/bash/runfiles/runfiles.bash " \
+            "$RUNFILES_MANIFEST_FILE" | cut -d ' ' -f 2-)"
+else
+  echo >&2 "ERROR: cannot find @bazel_tools//tools/bash/runfiles:runfiles.bash"
+  exit 1
+fi
+# --- end runfiles.bash initialization ---
+
+source "$(rlocation "io_bazel/src/test/shell/integration_test_setup.sh")" \
+  || { echo "integration_test_setup.sh not found!" >&2; exit 1; }
+
+case "$(uname -s | tr [:upper:] [:lower:])" in
+msys*|mingw*|cygwin*)
+  declare -r is_windows=true
+  ;;
+*)
+  declare -r is_windows=false
+  ;;
+esac
+
+if "$is_windows"; then
+  export MSYS_NO_PATHCONV=1
+  export MSYS2_ARG_CONV_EXCL="*"
+fi
+
+
+function test_default_java_toolchain_target_version() {
+  mkdir -p java/main
+  cat >java/main/BUILD <<EOF
+java_binary(
+    name = 'JavaBinary',
+    srcs = ['JavaBinary.java'],
+    main_class = 'JavaBinary',
+)
+load(
+    "@bazel_tools//tools/jdk:default_java_toolchain.bzl",
+    "default_java_toolchain",
+)
+default_java_toolchain(
+  name = "default_toolchain",
+  visibility = ["//visibility:public"],
+)
+EOF
+
+   cat >java/main/JavaBinary.java <<EOF
+public class JavaBinary {
+   public static void main(String[] args) {
+    System.out.println("Successfully executed JavaBinary!");
+  }
+}
+EOF
+  bazel run java/main:JavaBinary --java_toolchain=//java/main:default_toolchain --verbose_failures -s &>"${TEST_log}"
+  expect_log "Successfully executed JavaBinary!"
+  javap -verbose -cp bazel-bin/java/main/JavaBinary.jar JavaBinary | grep major &>"${TEST_log}"
+  expect_log "major version: 52"
+}
+
+run_suite "Java integration tests with default Bazel values"

tools/jdk/default_java_toolchain.bzl

@@ -79,6 +79,8 @@ DEFAULT_TOOLCHAIN_CONFIGURATION = {
     "compatible_javacopts": COMPATIBLE_JAVACOPTS,
     "singlejar": ["@bazel_tools//tools/jdk:singlejar"],
     "bootclasspath": ["@bazel_tools//tools/jdk:platformclasspath"],
+    "source_version": "8",
+    "target_version": "8",
 }
 
 def default_java_toolchain(name, **kwargs):