Offline build tooling (Makefile + JDK bootstrap)

.gitignore

@@ -101,6 +101,12 @@ fabric.properties
 *.tar.gz
 *.rar
 
+# local build output
+/build/
+
+# local JDK installs (bootstrapped)
+/.jdk/
+
 # virtual machine crash logs, see http://www.java.com/en/download/help/error_hotspot.xml
 hs_err_pid*
 

Makefile

@@ -0,0 +1,111 @@
+SHELL := bash
+
+SRC_DIR ?= client/src
+BUILD_DIR ?= build
+CLASSES_DIR ?= $(BUILD_DIR)/classes
+SOURCES_FILE ?= $(BUILD_DIR)/sources.txt
+
+LIBS ?= libs/clientlibs.jar
+MAIN_CLASS ?= Loader
+OUT_JAR ?= $(BUILD_DIR)/void-client.jar
+CLASSES_STAMP ?= $(CLASSES_DIR)/.compiled.stamp
+JAVA_ARGS ?=
+
+# Requested JDK major version. Used to validate JAVA_HOME and auto-select a bootstrapped JDK under ./.jdk/.
+JDK ?= 8
+BOOTSTRAP_JAVA_HOME ?= $(CURDIR)/.jdk/temurin$(JDK)
+
+# If JAVA_HOME isn't set (or doesn't match JDK), fall back to a repo-local bootstrapped JDK if present.
+JAVA_HOME_BIN_JAVA := $(JAVA_HOME)/bin/java
+JAVA_HOME_BIN_JAVAC := $(JAVA_HOME)/bin/javac
+
+ifdef JAVA_HOME
+  ifeq ($(wildcard $(JAVA_HOME_BIN_JAVA)),)
+    ifneq ($(wildcard $(BOOTSTRAP_JAVA_HOME)/bin/java),)
+      $(warning JAVA_HOME is set but invalid ($(JAVA_HOME_BIN_JAVA) missing); using $(BOOTSTRAP_JAVA_HOME))
+      JAVA_HOME := $(BOOTSTRAP_JAVA_HOME)
+    else
+      $(warning JAVA_HOME is set but invalid ($(JAVA_HOME_BIN_JAVA) missing); falling back to PATH)
+    endif
+  else
+    JAVA_HOME_MAJOR := $(shell "$(JAVA_HOME_BIN_JAVA)" -version 2>&1 | sed -n '1{s/.*version \"1\.\([0-9][0-9]*\).*/\1/p; s/.*version \"\([0-9][0-9]*\).*/\1/p;}')
+    ifneq ($(JAVA_HOME_MAJOR),$(JDK))
+      ifneq ($(wildcard $(BOOTSTRAP_JAVA_HOME)/bin/java),)
+        $(warning JAVA_HOME is Java $(JAVA_HOME_MAJOR) but JDK=$(JDK); using $(BOOTSTRAP_JAVA_HOME))
+        JAVA_HOME := $(BOOTSTRAP_JAVA_HOME)
+      else
+        $(warning JAVA_HOME is Java $(JAVA_HOME_MAJOR) but JDK=$(JDK); continuing with JAVA_HOME)
+      endif
+    endif
+  endif
+else
+  ifneq ($(wildcard $(BOOTSTRAP_JAVA_HOME)/bin/java),)
+    JAVA_HOME := $(BOOTSTRAP_JAVA_HOME)
+  endif
+endif
+
+ifdef JAVA_HOME
+JAVA := $(JAVA_HOME)/bin/java
+JAVAC := $(JAVA_HOME)/bin/javac
+JAR := $(JAVA_HOME)/bin/jar
+else
+JAVA ?= java
+JAVAC ?= javac
+JAR ?= jar
+endif
+
+.PHONY: help bootstrap sources compile jar run clean
+
+help:
+	@echo "Targets:"
+	@echo "  make bootstrap - download repo-local JDK (./.jdk/temurin\$$JDK)"
+	@echo "  make sources   - write $(SOURCES_FILE)"
+	@echo "  make compile   - compile $(SRC_DIR) into $(CLASSES_DIR)"
+	@echo "  make jar       - build runnable jar at $(OUT_JAR) (Main-Class: $(MAIN_CLASS))"
+	@echo "  make run       - run $(MAIN_CLASS) using $(OUT_JAR) + $(LIBS)"
+	@echo "  make clean     - remove $(BUILD_DIR)"
+	@echo ""
+	@echo "Vars:"
+	@echo "  JDK=8                    (requested major version; default 8)"
+	@echo "  JAVA_HOME=/path/to/jdk   (used if compatible with JDK; otherwise ./.jdk/temurin\$$JDK is preferred)"
+	@echo "  LIBS=libs/clientlibs.jar (classpath deps)"
+	@echo ""
+	@echo "Tip:"
+	@echo "  tools/bootstrap-jdk.sh \$$JDK  (downloads a repo-local JDK into .jdk/)"
+
+bootstrap:
+	@echo "Bootstrapping Temurin JDK $(JDK) into $(BOOTSTRAP_JAVA_HOME)"
+	@bash tools/bootstrap-jdk.sh "$(JDK)"
+
+JAVA_SOURCES := $(wildcard $(SRC_DIR)/*.java)
+LIB_JARS := $(subst :, ,$(LIBS))
+
+$(BUILD_DIR):
+	@mkdir -p "$@"
+
+$(CLASSES_DIR):
+	@mkdir -p "$@"
+
+sources: $(BUILD_DIR)
+	@find "$(SRC_DIR)" -maxdepth 1 -name '*.java' -print | sort > "$(SOURCES_FILE)"
+	@echo "Wrote $(SOURCES_FILE) ($$(wc -l < "$(SOURCES_FILE)") files)"
+
+$(CLASSES_STAMP): $(JAVA_SOURCES) $(LIB_JARS) | $(CLASSES_DIR) $(BUILD_DIR)
+	@echo "Compiling with: $(JAVAC)"
+	@find "$(SRC_DIR)" -maxdepth 1 -name '*.java' -print | sort > "$(SOURCES_FILE)"
+	@"$(JAVAC)" -Xlint:none -cp "$(LIBS)" -d "$(CLASSES_DIR)" @"$(SOURCES_FILE)"
+	@touch "$(CLASSES_STAMP)"
+
+compile: $(CLASSES_STAMP)
+
+$(OUT_JAR): $(CLASSES_STAMP) | $(BUILD_DIR)
+	@echo "Jarring to: $(OUT_JAR)"
+	@"$(JAR)" cfe "$(OUT_JAR)" "$(MAIN_CLASS)" -C "$(CLASSES_DIR)" .
+
+jar: $(OUT_JAR)
+
+run: $(OUT_JAR)
+	@"$(JAVA)" $(JAVA_ARGS) -cp "$(OUT_JAR):$(LIBS)" "$(MAIN_CLASS)"
+
+clean:
+	rm -rf "$(BUILD_DIR)"

tools/bootstrap-jdk.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+JDK_MAJOR="${1:-8}"
+
+case "${JDK_MAJOR}" in
+  8|11|17|21) ;;
+  *)
+    echo "Usage: tools/bootstrap-jdk.sh {8|11|17|21}"
+    echo "Downloads an Eclipse Temurin JDK into $ROOT_DIR/.jdk/temurin<JDK_MAJOR> (no Gradle, no system install)."
+    exit 2
+    ;;
+esac
+
+OS="linux"
+ARCH_RAW="$(uname -m)"
+case "$ARCH_RAW" in
+  x86_64|amd64) ARCH="x64" ;;
+  aarch64|arm64) ARCH="aarch64" ;;
+  *)
+    echo "Unsupported arch: $ARCH_RAW"
+    exit 2
+    ;;
+esac
+
+DEST_DIR="$ROOT_DIR/.jdk/temurin${JDK_MAJOR}"
+TMP_DIR="${DEST_DIR}.tmp.$$"
+ARCHIVE="/tmp/temurin${JDK_MAJOR}-${OS}-${ARCH}-jdk.tar.gz"
+
+URL="https://api.adoptium.net/v3/binary/latest/${JDK_MAJOR}/ga/${OS}/${ARCH}/jdk/hotspot/normal/eclipse"
+
+echo "Downloading Temurin JDK ${JDK_MAJOR} for ${OS}/${ARCH}..."
+echo "  $URL"
+curl -fsSL -o "$ARCHIVE" "$URL"
+
+rm -rf "$TMP_DIR"
+mkdir -p "$TMP_DIR"
+
+echo "Extracting to $DEST_DIR ..."
+tar -xzf "$ARCHIVE" -C "$TMP_DIR" --strip-components=1
+
+rm -rf "$DEST_DIR"
+mv "$TMP_DIR" "$DEST_DIR"
+
+cat <<EOF
+Done.
+
+Use it for builds:
+  export JAVA_HOME="$DEST_DIR"
+  export PATH="\$JAVA_HOME/bin:\$PATH"
+
+Then:
+  make jar
+or:
+  tools/build.sh
+EOF
+

tools/build.sh

@@ -0,0 +1,39 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+SRC_DIR="${SRC_DIR:-"$ROOT_DIR/client/src"}"
+BUILD_DIR="${BUILD_DIR:-"$ROOT_DIR/build"}"
+CLASSES_DIR="${CLASSES_DIR:-"$BUILD_DIR/classes"}"
+SOURCES_FILE="${SOURCES_FILE:-"$BUILD_DIR/sources.txt"}"
+
+LIBS="${LIBS:-"$ROOT_DIR/libs/clientlibs.jar"}"
+MAIN_CLASS="${MAIN_CLASS:-Loader}"
+OUT_JAR="${OUT_JAR:-"$BUILD_DIR/void-client.jar"}"
+
+JAVA_BIN="${JAVA_HOME:+$JAVA_HOME/bin/}java"
+JAVAC_BIN="${JAVA_HOME:+$JAVA_HOME/bin/}javac"
+JAR_BIN="${JAVA_HOME:+$JAVA_HOME/bin/}jar"
+
+EXCLUDE_REGEX="${EXCLUDE_REGEX:-}"
+
+mkdir -p "$BUILD_DIR" "$CLASSES_DIR"
+
+find "$SRC_DIR" -maxdepth 1 -name '*.java' -print | sort > "$SOURCES_FILE"
+if [[ -n "$EXCLUDE_REGEX" ]]; then
+  grep -Ev "$EXCLUDE_REGEX" "$SOURCES_FILE" > "$SOURCES_FILE.tmp"
+  mv "$SOURCES_FILE.tmp" "$SOURCES_FILE"
+fi
+
+echo "Sources: $(wc -l < "$SOURCES_FILE") ($SOURCES_FILE)"
+echo "JAVAC: $JAVAC_BIN"
+
+"$JAVAC_BIN" -Xlint:none -cp "$LIBS" -d "$CLASSES_DIR" @"$SOURCES_FILE"
+
+echo "JAR: $OUT_JAR"
+"$JAR_BIN" cfe "$OUT_JAR" "$MAIN_CLASS" -C "$CLASSES_DIR" .
+
+echo "Done. Run with:"
+echo "  $JAVA_BIN -cp $OUT_JAR:$LIBS $MAIN_CLASS"
+

tools/run.sh

@@ -0,0 +1,24 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+BUILD_DIR="${BUILD_DIR:-"$ROOT_DIR/build"}"
+LIBS="${LIBS:-"$ROOT_DIR/libs/clientlibs.jar"}"
+MAIN_CLASS="${MAIN_CLASS:-Loader}"
+OUT_JAR="${OUT_JAR:-"$BUILD_DIR/void-client.jar"}"
+
+JAVA_BIN="${JAVA_HOME:+$JAVA_HOME/bin/}java"
+JAVA_ARGS="${JAVA_ARGS:-}"
+
+read -r -a JAVA_ARGS_ARR <<<"$JAVA_ARGS"
+
+if [[ ! -f "$OUT_JAR" ]]; then
+  echo "Missing $OUT_JAR. Build first with:"
+  echo "  make jar"
+  echo "or"
+  echo "  tools/build.sh"
+  exit 1
+fi
+
+exec "$JAVA_BIN" "${JAVA_ARGS_ARR[@]}" -cp "$OUT_JAR:$LIBS" "$MAIN_CLASS" "$@"