Java की सामान्य गलतियाँ

public class Main {
	public static void main(String[] args) {
		String a = new String("hi");
		String b = new String("hi");
		System.out.println(a == b); // false: different objects
		System.out.println(a.equals(b)); // true: same content
	}
}

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// Define the class Main
public class Main {
	// Program entry point: the JVM starts running here
	public static void main(String[] args) {
		// Declare value and set it to null
		String value = null;
		// Try code that might throw an exception
		try {
			value.length();
		// Handle NullPointerException if it was thrown
		} catch (NullPointerException e) {
			// Print a line to the console
			System.out.println("Caught NullPointerException");
		}
	}
}

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// Import java.util.ArrayList so it can be used by its short name
import java.util.ArrayList;
// Define the class Main
public class Main {
	// Program entry point: the JVM starts running here
	public static void main(String[] args) {
		// Create a new ArrayList object and store it in list
		ArrayList<Integer> list = new ArrayList<>(java.util.List.of(1, 2, 3));
		// Try code that might throw an exception
		try {
			for (Integer n : list) {
				list.remove(n);
			}
		// Handle java.util.ConcurrentModificationException if it was thrown
		} catch (java.util.ConcurrentModificationException e) {
			// Print a line to the console
			System.out.println("Caught: use Iterator.remove() instead");
		}
	}
}

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public class Main {
	public static void main(String[] args) {
		int[] arr = {1, 2, 3};
		try {
			System.out.println(arr[3]); // size itself is one past the last valid index
		} catch (ArrayIndexOutOfBoundsException e) {
			System.out.println("Caught: index out of bounds");
		}
	}
}

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public class Main {
	public static void main(String[] args) {
		System.out.println(5 / 2); // 2: truncated
		System.out.println(5 / (double) 2); // 2.5: cast avoids truncation
	}
}

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