NOISSUE Fail launch if minimum Java requirement is not met

This will fail launch in the following conditions:
  1. A version greater than or equal to Minecraft 17w13a, and less than
     21w19a - and the Java version is less than 8.
  2. A version greater than or equal to Minecraft 21w19a - and the Java
     version is less than 16.

2 files changed, 51 insertions, 0 deletions

diff --git a/api/logic/minecraft/launch/VerifyJavaInstall.cpp b/api/logic/minecraft/launch/VerifyJavaInstall.cpp
new file mode 100644
index 00000000..657669af
--- /dev/null
+++ b/api/logic/minecraft/launch/VerifyJavaInstall.cpp
@@ -0,0 +1,34 @@
+#include "VerifyJavaInstall.h"
+
+#include <launch/LaunchTask.h>
+#include <minecraft/MinecraftInstance.h>
+#include <minecraft/PackProfile.h>
+#include <minecraft/VersionFilterData.h>
+
+void VerifyJavaInstall::executeTask() {
+    auto m_inst = std::dynamic_pointer_cast<MinecraftInstance>(m_parent->instance());
+
+    auto javaVersion = m_inst->getJavaVersion();
+    auto minecraftComponent = m_inst->getPackProfile()->getComponent("net.minecraft");
+
+    // Java 16 requirement
+    if (minecraftComponent->getReleaseDateTime() >= g_VersionFilterData.java16BeginsDate) {
+        if (javaVersion.major() < 16) {
+            emit logLine("Minecraft 21w19a and above require the use of Java 16",
+                         MessageLevel::Fatal);
+            emitFailed(tr("Minecraft 21w19a and above require the use of Java 16"));
+            return;
+        }
+    }
+    // Java 8 requirement
+    else if (minecraftComponent->getReleaseDateTime() >= g_VersionFilterData.java8BeginsDate) {
+        if (javaVersion.major() < 8) {
+            emit logLine("Minecraft 17w13a and above require the use of Java 8",
+                         MessageLevel::Fatal);
+            emitFailed(tr("Minecraft 17w13a and above require the use of Java 8"));
+            return;
+        }
+    }
+
+    emitSucceeded();
+}
diff --git a/api/logic/minecraft/launch/VerifyJavaInstall.h b/api/logic/minecraft/launch/VerifyJavaInstall.h
new file mode 100644
index 00000000..a553106d
--- /dev/null
+++ b/api/logic/minecraft/launch/VerifyJavaInstall.h
@@ -0,0 +1,17 @@
+#pragma once
+
+#include <launch/LaunchStep.h>
+
+class VerifyJavaInstall : public LaunchStep {
+    Q_OBJECT
+
+public:
+    explicit VerifyJavaInstall(LaunchTask *parent) : LaunchStep(parent) {
+    };
+    ~VerifyJavaInstall() override = default;
+
+    void executeTask() override;
+    bool canAbort() const override {
+        return false;
+    }
+};