Add GWT helper script for command line development

.gitignore

@@ -5,6 +5,10 @@ war/circuitjs1/circuits/
 war/e-*.html
 war/WEB-INF/
 
+# GWT command line tools
+codeserver.log
+webserver.log
+
 # Windows image file caches
 Thumbs.db
 ehthumbs.db

gwt.sh

@@ -0,0 +1,76 @@
+#!/bin/bash
+set -o errexit -o nounset
+
+SCRIPT_DIR="$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")"
+WORK_DIR="../workdir"
+SDK_DIR=".."
+GWT_VERSION="2.10.0"
+GWT="$SDK_DIR/gwt-$GWT_VERSION"
+
+compile() {
+    ant build
+}
+
+setup() {
+    # Install Java if no java compiler is present
+    if ! which javac > /dev/null 2>&1; then
+        echo "Installing packages may need your sudo password."
+        set -x
+        sudo apt install openjdk-8-jdk-headless
+        set +x
+    fi
+
+    if ! [[ -d "$SDK_DIR" ]]; then
+        mkdir -p "$SDK_DIR"
+        cd "$SDK_DIR"
+        wget "https://github.com/gwtproject/gwt/releases/download/$GWT_VERSION/gwt-$GWT_VERSION.zip"
+        unzip "gwt-$GWT_VERSION.zip"
+        rm "gwt-$GWT_VERSION.zip"
+        set +x
+    fi
+
+    if ! [[ -e build.xml ]]; then
+        chmod +x "$GWT/webAppCreator"
+        "$GWT/webAppCreator" -out ../tempProject com.lushprojects.circuitjs1.circuitjs1
+        cp ../tempProject/build.xml .
+        rm -rf ../tempProject
+    fi
+}
+
+codeserver() {
+    mkdir -p war
+    java -classpath "src:$GWT/gwt-codeserver.jar:$GWT/gwt-dev.jar:$GWT/gwt-user.jar" \
+        com.google.gwt.dev.codeserver.CodeServer \
+        -launcherDir war \
+        com.lushprojects.circuitjs1.circuitjs1
+}
+
+webserver() {
+    sourcedir="$(dirname "$(readlink -f "${BASH_SOURCE[0]}")")"
+    #webroot="workdir/com.lushprojects.circuitjs1.circuitjs1/compile-1/war"
+    webroot="war"
+
+    #cp -r "$sourcedir/war/"*.html "$webroot"
+    cd $webroot
+    python -m http.server
+}
+
+start() {
+    webserver >"webserver.log" 2>&1 &
+    PID=$!
+    codeserver | tee "codeserver.log"
+    kill -INT "$PID"
+}
+
+
+for func in $(compgen -A function); do
+    if [[ $func == "$1" ]]; then
+        shift
+        $func "$@"
+        exit $?
+    fi
+done
+
+echo "Unknown command '$1'. Try one of the following:"
+compgen -A function
+exit 1