nuke-java

#!/usr/bin/env bash

set -u

jdk_dirs=(
  "/Library/Java/JavaVirtualMachines"
  "$HOME/Library/Java/JavaVirtualMachines"
  "$HOME/Library/Java"
  "$HOME/.jdks"
  "$HOME/.sdkman/candidates/java"
  "$HOME/.asdf/installs/java"
  "$HOME/.jenv/versions"
  "/opt/homebrew/opt"
  "/usr/local/opt"
)

declare -a found_jdks=()
enable_delete=false

while [[ $# -gt 0 ]]; do
  case "$1" in
    --delete|-d)
      enable_delete=true
      shift
      ;;
    *)
      echo "Unknown option: $1"
      echo "Usage: $0 [--delete|-d]"
      exit 1
      ;;
  esac
done

echo "Scanning for installed JDKs..."
echo

for dir in "${jdk_dirs[@]}"; do
  if [[ -d "$dir" ]]; then
    while IFS= read -r -d '' jdk; do
      # For Homebrew/opt and usr/local/opt, we only care about openjdk and java directories
      if [[ ("$dir" == "/opt/homebrew/opt" || "$dir" == "/usr/local/opt") && ! ("$(basename "$jdk")" == openjdk* || "$(basename "$jdk")" == java) ]]; then
        continue
      fi

      # Check if it has bin/java or Contents/Home/bin/java or libexec/openjdk.jdk/Contents/Home/bin/java
      if [[ -e "$jdk/bin/java" || -e "$jdk/Contents/Home/bin/java" || -e "$jdk/libexec/openjdk.jdk/Contents/Home/bin/java" ]]; then
        found_jdks+=("$jdk")
      fi
    done < <(find "$dir" -mindepth 1 -maxdepth 1 \( -type d -o -type l \) -print0 2>/dev/null)
  fi
done

if [[ ${#found_jdks[@]} -eq 0 ]]; then
  echo "No JDK bundles found."
  exit 0
fi

echo "Found ${#found_jdks[@]} JDK(s):"
echo

for i in "${!found_jdks[@]}"; do
  jdk="${found_jdks[$i]}"
  java_bin="$jdk/Contents/Home/bin/java"
  if [[ ! -x "$java_bin" ]]; then
    java_bin="$jdk/bin/java"
  fi
  if [[ ! -x "$java_bin" ]]; then
    java_bin="$jdk/libexec/openjdk.jdk/Contents/Home/bin/java"
  fi

  echo "[$((i+1))] $jdk"

  if [[ -x "$java_bin" ]]; then
    version_output="$("$java_bin" -version 2>&1 | head -n 2)"
    echo "$version_output" | sed 's/^/    /'
  else
    echo "    Warning: no java executable found in this bundle"
  fi

  echo
done

if [[ "$enable_delete" == true ]]; then
  for jdk in "${found_jdks[@]}"; do
    echo "JDK: $jdk"
    read -r -p "Delete this JDK? [y/N] " reply

    case "$reply" in
      y|Y|yes|YES)
        if [[ "$jdk" == /Library/Java/JavaVirtualMachines/* ]]; then
          echo "Deleting with sudo: $jdk"
          sudo rm -rf "$jdk"
        else
          echo "Deleting: $jdk"
          rm -rf "$jdk"
        fi
        echo "Deleted."
        ;;
      *)
        echo "Kept."
        ;;
    esac

    echo
  done
else
  echo "Deletion skipped. Use --delete or -d to enable interactive deletion."
  echo
fi

echo "Remaining JDKs:"
/usr/libexec/java_home -V 2>&1 || true