Java 25 New Features — What Changed and Why Minecraft Upgraded

package io.thecodeforge.monitoring;

import java.lang.management.ManagementFactory;
import java.lang.management.GarbageCollectorMXBean;
import java.util.List;

/**
 * A simple utility to verify the active Garbage Collector.
 * No more guessing if ZGC is actually doing the heavy lifting.
 */
public class GCChecker {
    public static void main(String[] args) {
        List<GarbageCollectorMXBean> gcBeans = ManagementFactory.getGarbageCollectorMXBeans();
        
        System.out.println("--- TheCodeForge Runtime Monitor ---");
        System.out.println("Active Garbage Collectors for this JVM instance:");
        
        for (GarbageCollectorMXBean bean : gcBeans) {
            System.out.printf(" - %s (Collections: %d, Total Time: %dms)%n", 
                bean.getName(), 
                bean.getCollectionCount(), 
                bean.getCollectionTime());
        }
    }
}

# Production Dockerfile for Java 25 applications
# We use the Temurin distribution for stable LTS support
FROM eclipse-temurin:25-jdk-jammy

WORKDIR /app
COPY target/forge-service.jar app.jar

# Pro-tip: Java 25 automatically optimizes object headers on 64-bit systems.
# You can verify this in logs by adding -Xlog:cds=debug during startup.
ENTRYPOINT ["java", "-Xmx2g", "-jar", "app.jar"]

package io.thecodeforge.logic;

public class ShapeProcessor {
    // Sealed hierarchy ensures the switch is exhaustive at compile-time
    public sealed interface Shape permits Circle, Rectangle, Triangle {}
    public record Circle(double radius) implements Shape {}
    public record Rectangle(double width, double height) implements Shape {}
    public record Triangle(double base, double height) implements Shape {}

    public static double calculateArea(Shape shape) {
        return switch (shape) {
            case Circle c    -> Math.PI * Math.pow(c.radius(), 2);
            case Rectangle r -> r.width() * r.height();
            case Triangle t  -> 0.5 * t.base() * t.height();
            // Default is unnecessary and actually discouraged with sealed types!
        };
    }

    public static String categorizeInput(Object obj) {
        return switch (obj) {
            case Integer i when i > 100 -> "High-capacity Integer";
            case Integer i -> "Standard Integer";
            case String s when s.isBlank() -> "Empty input string";
            case String s -> "Valid string: " + s;
            case null -> "Null reference detected";
            default -> "Unsupported type";
        };
    }
}

package io.thecodeforge.models;

public class PatternDemo {
    record Point(int x, int y) {}
    record Window(Point topLeft, Point bottomRight) {}

    public static void printDiagnostics(Object obj) {
        // Nesting record patterns for deep destructuring
        if (obj instanceof Window(Point(int x1, int y1), Point(int x2, int y2))) {
            int width = Math.abs(x2 - x1);
            int height = Math.abs(y2 - y1);
            System.out.printf("Rendering Window [%dx%d] starting at (%d,%d)%n", width, height, x1, y1);
        }
    }
}

package io.thecodeforge.web;

import java.util.concurrent.ExecutorService;
import java.util.concurrent.Executors;

public class ConcurrencyConfig {
    
    /**
     * Returns an executor that spawns a new virtual thread for every task.
     * Ideal for blocking I/O operations like database queries or REST calls.
     */
    public static ExecutorService getVirtualExecutor() {
        return Executors.newVirtualThreadPerTaskExecutor();
    }

    public void handleAsyncRequest(Runnable task) {
        // Lightweight thread creation
        Thread.ofVirtual()
              .name("forge-worker-", 1)
              .start(task);
    }
}

# 1. Install Java 25 (Temurin) via SDKMAN
sdk install java 25-tem
sdk default java 25-tem

# 2. Update your Maven pom.xml
# <properties>
#   <java.version>25</java.version>
#   <maven.compiler.release>25</maven.compiler.release>
# </properties>

# 3. Or update your Gradle build.gradle
# java {
#     toolchain {
#         languageVersion = JavaLanguageVersion.of(25)
#     }
# }

# 4. Clean and verify
./mvnw clean verify