Fix Java version issue

Added option to run with specific Java version or auto-decided Java for to fix #2

Author: HoodedDeath

README.md

@@ -147,7 +147,7 @@ Many thanks to both projects for making this one possible.
 - 1.3.1
   - Fixed memory allocation issue which was causing servers to always be limited to 1G memory
     - Setting memory within `JVM_OPTS` using the `-Xmx` and `-Xms` flags fails to set memory, using docker flags `MAX_MEMORY` and `INIT_MEMORY` works properly
-    - Within the start-minecraftFinalSetup file from https://github.com/itgz/docker-minecraft-server/ (line 155 as of March 13, 2021), the setup overrides the `-Xmx` and `-Xms` JVM flags using the `MAX_MEMORY` and `INIT_MEMORY` variables
+    - Within the start-minecraftFinalSetup file from https://github.com/itzg/docker-minecraft-server/ (line 155 as of March 13, 2021), the setup overrides the `-Xmx` and `-Xms` JVM flags using the `MAX_MEMORY` and `INIT_MEMORY` variables
 - 1.4
   - Updated template-vars file with some additional settings and better comments on settings
     - Added WORLD and SPAWN_PROTECTION settings
@@ -165,4 +165,9 @@ Many thanks to both projects for making this one possible.
   - Added `print-environment` and `print-var` commands to script to print out all variables or a specific variable respectively
   - Removed copying server icon from file, as it was not working without changing write permissions within server directory
   - Removed `follow-log` command, functionality moved to `log --follow`
-  - General reworking of script
+  - General reworking of script
+- 1.5.1
+  - Adjusted `print-environment` output
+  - Added `--version` option to output version of script
+  - Added `JAVA_VERSION` option to variables file
+    - Reworked start function to utilize `JAVA_VERSION` option

src/minecraftctl.sh

@@ -1,8 +1,10 @@
 #!/bin/bash
 # Names of variables that should have a non-null default value
-name_arr=("DOCKER" "PORT" "RCON_PORT" "RCON_PASSWORD" "MINHEAP" "MAXHEAP" "EULA" "TYPE" "VERSION" "DIFFICULTY" "MAX_PLAYERS" "MAX_WORLD_SIZE" "ALLOW_NETHER" "ANNOUNCE_PLAYER_ACHIEVEMENTS" "ENABLE_COMMAND_BLOCK" "FORCE_GAMEMODE" "GENERATE_STRUCTURES" "HARDCORE" "MAX_BUILD_HEIGHT" "MAX_TICK_TIME" "SPAWN_MONSTERS" "SPAWN_NPCS" "VIEW_DISTANCE" "MODE" "MOTD" "PVP" "LEVEL_TYPE" "LEVEL" "AUTOPAUSE" "TIMEOUT" "EPHEMERAL" "DATA_DIR" "BACKUP_DIR" "SPAWN_PROTECTION" "MINECRAFT_UID" "MINECRAFT_GID")
+name_arr=("DOCKER" "PORT" "RCON_PORT" "RCON_PASSWORD" "MINHEAP" "MAXHEAP" "EULA" "TYPE" "VERSION" "DIFFICULTY" "MAX_PLAYERS" "MAX_WORLD_SIZE" "ALLOW_NETHER" "ANNOUNCE_PLAYER_ACHIEVEMENTS" "ENABLE_COMMAND_BLOCK" "FORCE_GAMEMODE" "GENERATE_STRUCTURES" "HARDCORE" "MAX_BUILD_HEIGHT" "MAX_TICK_TIME" "SPAWN_MONSTERS" "SPAWN_NPCS" "VIEW_DISTANCE" "MODE" "MOTD" "PVP" "LEVEL_TYPE" "LEVEL" "AUTOPAUSE" "TIMEOUT" "EPHEMERAL" "DATA_DIR" "BACKUP_DIR" "SPAWN_PROTECTION" "MINECRAFT_UID" "MINECRAFT_GID" "JAVA_VERSION")
 # Default values for variables in above array
-vals_arr=("$(which docker)" "25565" "25575" "minecraft" "512" "2048" "false" "vanilla" "LATEST" "normal" "10" "29999984" "true" "true" "false" "false" "true" "false" "256" "60000" "true" "true" "10" "survival" "A minecraft server" "true" "default" "world" "true" "0" "false" "/srv/minecraft" "./backups" "64" "$(id -u minecraft)" "$(id -g minecraft)")
+vals_arr=("$(which docker)" "25565" "25575" "minecraft" "512" "2048" "false" "vanilla" "LATEST" "normal" "10" "29999984" "true" "true" "false" "false" "true" "false" "256" "60000" "true" "true" "10" "survival" "A minecraft server" "true" "default" "world" "true" "0" "false" "/srv/minecraft" "./backups" "64" "$(id -u minecraft)" "$(id -g minecraft)" "DEFAULT")
+# Version string
+VERSION_STR="1.5.1"
 # Setup flag variables for script
 seteula=false
 debug=false
@@ -18,6 +20,7 @@ function usage {
     echo "  -e <TRUE|FALSE> | --eula <TRUE|FALSE>: Set Eula to a desired value, regardless of environment file. Useful for starting a default environment server that doesn't need an environment file just for the EULA option."
     echo "  -f | --follow: Follows the log of the docker container when used with the 'log' command"
     echo "  -v | --verbose: Enables verbosity messages about what is happening"
+    echo "  -V | --version: Prints version"
     echo
     echo "Actions:"
     echo "  help | usage"
@@ -57,9 +60,26 @@ function usage {
 }
 # Print environment variables
 function printvars {
-    for i in ${!name_arr[@]}; do
-        echo "${name_arr[$i]} - Default: ${vals_arr[$i]} - Currently: ${!name_arr[$i]}"
+  for i in ${!name_arr[@]}; do
+    len=${#name_arr[$i]}
+    echo -n "${name_arr[$i]}"
+    for j in {0..28}; do
+      # echo -n " "
+      if [[ $j -gt $len ]]; then
+        echo -n " "
+      fi
+    done
+    echo -n " - Default: "
+    len=${#vals_arr[$i]}
+    echo -n "${vals_arr[$i]}"
+    for j in {0..18}; do
+      # echo -n " "
+      if [[ $j -gt $len ]]; then
+        echo -n " "
+      fi
     done
+    echo " - Current: ${!name_arr[$i]}"
+  done
 }
 # Print a specific environment variable
 function printvar {
@@ -93,6 +113,7 @@ function status {
     if [[ "x$name" == "xall" ]]; then
         vmsg "Finding docker containers ..."
         servers=($(docker ps --filter ancestor=itzg/minecraft-server:java8 --format "{{.Names}}"))
+        servers+=($(docker ps --filter ancestor=itzg/minecraft-server:java16 --format "{{.Names}}"))
         dmsg "Containers found: [ ${servers[@]} ]"
         for i in ${!servers[@]}; do
             vmsg "Testing container '${servers[$i]}'"
@@ -102,6 +123,7 @@ function status {
                 echo "Server '${servers[$i]}' is stopped"
             fi
         done
+        exit 0
     else
         vmsg "Testing container '$name' for running status ..."
     	if running; then
@@ -137,7 +159,40 @@ function start {
         vol_mount=""
         echo "Ephemeral server, a restart will lose all world data."
     fi
+
+    vmsg "Deciding Java version to use ..."
+    if [[ "$JAVA_VERSION" == "DEFAULT" ]]; then
+        # Check for game version
+        dmsg "Java version set to default. Checking game version ..."
+        if [[ $VERSION == "LATEST" ]] || [[ $VERSION == "SNAPSHOT" ]]; then
+            dmsg "Game version set to $VERSION. Setting Java version to latest."
+            jvm_ver="latest"
+        else
+            dmsg "Game version is $VERSION. Splitting version string to check for usable Java version ..."
+            if [[ ! -z $IFS ]]; then
+                OLD_IFS=$IFS
+                reset_ifs=true
+            fi
+            IFS="."
+            # Split game version string from (example) 1.17.1 to an array as [ 1 17 1 ]
+            readarray -t ver_arr <<< $VERSION
+            ver_arr=($ver_arr)
+            IFS=$OLD_IFS
+            # Check if game is 1.17 or higher, as that is the point when Java16 is required
+            if [[ ${ver_arr[1]} -ge 17 ]]; then
+                dmsg "Game version is at least 1.17. Setting Java version to Java16."
+                jvm_ver="java16"
+            else
+                dmsg "Game version is below 1.17. Setting Java version to Java8."
+                jvm_ver="java8"
+            fi
+        fi
+    else
+        dmsg "Java version has been manually specified. Running with specification."
+        jvm_ver="$JAVA_VERSION"
+    fi
     vmsg "Calling '$DOCKER' to start server container '$name' ..."
+    # Maybe remove that default port from ports? might not be needed
     $DOCKER run -d -i \
         --name "$name" \
         $vol_mount \
@@ -181,7 +236,7 @@ function start {
         -e "ENABLE_AUTOPAUSE=$AUTOPAUSE" \
         -e "TIMEOUT=$TIMEOUT" \
         -e "SPAWN_PROTECTION=$SPAWN_PROTECTION" \
-        itzg/minecraft-server:java8
+        itzg/minecraft-server:$jvm_ver
     echo "Started minecraft container '$name'"
 }
 # Send a command to the game server
@@ -305,7 +360,7 @@ function check_vars {
     done
     # Set the rcon command now that password and port are set either to user-defined or default values
     RCON_CMD="mcrcon -P ${RCON_PORT} -p ${RCON_PASSWORD}"
-    dmsg "Setting RCON_CMD to '$RCON_CMD'"
+    dmsg "Set RCON_CMD to '$RCON_CMD'"
 }
 
 # Exit immediately if a command exits with non-zero status
@@ -314,6 +369,7 @@ set -e
 # Check valid command before other steps
 case $1 in
     status|start|stop|restart|backup|save|command|console|log|help|usage|print-environment|print-var) if [[ "$@" == *"-d"* ]] || [[ "$@" == *"--debug"* ]]; then echo "Command recognized as $1"; fi; cmd=$1; shift;;
+    -V|--version) echo "$VERSION_STR"; exit 0;;
     *) usage;;
 esac
 # Command line options

src/template-vars

@@ -27,6 +27,9 @@
 # Game version - can be set to LATEST, SNAPSHOT, or a specific version number
 #VERSION="LATEST"
 
+# Java version to use - can be set to DEFAULT, latest, or a specific version, such as java8 or java16 - see https://github.com/itzg/docker-minecraft-server#running-minecraft-server-on-different-java-version for full list of supported versions
+#JAVA_VERSION="DEFAULT"
+
 # Game difficulty
 #DIFFICULTY="normal"
 
@@ -121,4 +124,4 @@
 #DATA_DIR="/srv/minecraft"
 
 # Relative directory to $DATA_DIR for saving minecraft backups
-#BACKUP_DIR="./backups"
+#BACKUP_DIR="./backups"