Java में Memory Management

public class Main {
	static class Point { int x; } // instances live on the Heap
	public static void main(String[] args) {
		int localVar = 5; // lives on the Stack, cleaned up when main() returns
		Point p = new Point(); // the reference is on the Stack, the object itself is on the Heap
		System.out.println(localVar + " " + p);
	}
}

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import java.util.*;
public class Main {
	static List<Object> cache = new ArrayList<>(); // static list -- keeps growing, never cleared
	public static void main(String[] args) {
		for (int i = 0; i < 5; i++) cache.add(new Object());
		System.out.println("Cache size: " + cache.size() + " -- these can never be garbage collected");
	}
}

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public class Main {
	public static void main(String[] args) {
		try {
			int[] huge = new int[Integer.MAX_VALUE]; // exceeds available heap
		} catch (OutOfMemoryError e) {
			System.out.println("Caught OutOfMemoryError: heap exceeded");
		}
	}
}

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public class Main {
	public static void main(String[] args) {
		// Run with: java -XX:MaxMetaspaceSize=128m Main
		System.out.println("Class metadata lives in Metaspace, drawn from native memory, not the heap");
	}
}

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// Import java.lang.ref.Cleaner so it can be used by its short name
import java.lang.ref.Cleaner;
// Define the class Main
public class Main {
	static final Cleaner cleaner = Cleaner.create();
	// Program entry point: the JVM starts running here
	public static void main(String[] args) {
		// Create a new Object object and store it in resource
		Object resource = new Object();
		cleaner.register(resource, () -> System.out.println("Cleaned up off-heap resource"));
		resource = null;
		System.gc();
	}
}

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