build(CI): do not install java versions included in ubuntu image to speed up CI 🤖

Author: oldratlee

.github/workflows/strong_ci.yaml

@@ -20,13 +20,10 @@ jobs:
         with:
           # https://github.com/actions/setup-java?tab=readme-ov-file#install-multiple-jdks
           #
-          # do NOT move old version 8.0.345 before 8, because the old version satisfied version 8
+          # image(ubuntu-latest/ubuntu-24.04) included Java 8/11/17/21/25
+          #   https://github.com/actions/runner-images/blob/main/images/ubuntu/Ubuntu2404-Readme.md#java
           java-version: |
-            8
             8.0.345
-            11
-            17
-            21
             23
           distribution: zulu
           cache: maven

scripts/integration_test

@@ -29,18 +29,12 @@ _findJdk8_0_345() {
   # https://docs.github.com/en/actions/learn-github-actions/variables#default-environment-variables
   if [ true = "${GITHUB_ACTIONS:-}" ]; then
     JAVA8_0_345_HOME="$(
-      d="$(echo "$JAVA8_HOME/../.."/8.0.345*/x64)" || cu::die "Fail to get java home of v8.0.345!"
+      d="$(echo /opt/hostedtoolcache/*/8.0.345*/x64)" || cu::die "Fail to get java home of v8.0.345!"
       cd "$d" || cu::die "Fail to cd java home of v8.0.345($d)!"
       pwd
     )"
 
-    JDK_8_LATEST="$(
-      # shellcheck disable=SC2012
-      d="$(ls -v -d "$JAVA8_HOME/../.."/8.* | tail -n 1)" || cu::die "Fail to get latest java 8 home!"
-      cd "$d" || cu::die "Fail to cd java8 home"
-      pwd
-    )/x64"
-
+    JDK_8_LATEST="$(echo /usr/lib/jvm/*-8-jdk-*)"
     [ "$JDK_8_LATEST" != "$JAVA8_0_345_HOME" ] || cu::die "JDK_8_LATEST($JDK_8_LATEST) is same as JAVA8_0_345_HOME($JAVA8_0_345_HOME), NOT newer java 8 version!"
     export JAVA8_HOME="$JDK_8_LATEST"
   else