Set correct source/target java versions

Co-authored-by: Howard ZHY <96782166+howardzhy@users.noreply.github.com>

build.gradle

@@ -33,6 +33,10 @@ allprojects {
         toolchain.languageVersion = JavaLanguageVersion.of(21)
     }
 
+    // Always set min java version to 17, for java 8 versions the jar is manually downgraded so it doesn't matter.
+    compileJava.setSourceCompatibility("17")
+    compileJava.setTargetCompatibility("17")
+
     // Configuration used to include dependencies to the final jars
     configurations {
         library
@@ -95,6 +99,11 @@ subprojects {
     // Used to execute code only for specific submodules
     def versionId = Integer.parseInt(mcVersion.replace(".", ""))
 
+    // Java 17 is default, set newer versions here
+    if (versionId >= 1_20_6) {
+        compileJava.setSourceCompatibility("21")
+        compileJava.setTargetCompatibility("21")
+    }
     compileJava.options.encoding = "UTF-8"
 
     minecraft {
@@ -140,7 +149,9 @@ subprojects {
             library "org.spongepowered:mixin:${mixin_version}"
             annotationProcessor "org.spongepowered:mixin:${mixin_version}:processor"
         }
+
         if (versionId >= 1_20_6) {
+            // NeoForge, only to compile against
             compileOnly("net.neoforged.fancymodloader:loader:2.0.20") { transitive = false }
             compileOnly("net.neoforged:bus:7.2.0") { transitive = false }
         }
@@ -283,4 +294,4 @@ subprojects {
 
 dependencies {
     compileOnly "io.netty:netty-all:4.1.117.Final"
-}
+}

settings.gradle

@@ -12,4 +12,8 @@ include "viaforge-mc1192"
 include "viaforge-mc1194"
 include "viaforge-mc1204"
 include "viaforge-mc1206"
-include "viaforge-mc1214"
+include "viaforge-mc1214"
+
+plugins {
+    id "org.gradle.toolchains.foojay-resolver-convention" version "0.9.0"
+}