Interview question

What is the difference between throw and throws in Java? Java में throw और throws में क्या अंतर है?

Answer

Keyword	Used for	Location	Number allowed
throw	Actually throwing an exception instance	Inside a method body	One exception object per throw statement
throws	Declaring that a method MIGHT throw an exception	In the method signature	Multiple exceptions, comma-separated

import java.io.IOException;
import java.sql.SQLException;

// 'throws' - declares possible exceptions in the method signature
public void processFile(String path) throws IOException, SQLException {
    if (path == null) {
        // 'throw' - actually creates and throws an exception instance
        throw new IllegalArgumentException('Path cannot be null');
    }
    // ... code that might throw IOException or SQLException ...
}

// Caller must handle or re-declare the checked exceptions
public void caller() {
    try {
        processFile('data.txt');
    } catch (IOException | SQLException e) {  // multi-catch (Java 7+)
        System.out.println('Error: ' + e.getMessage());
    }
}

// 'throw' can also re-throw a caught exception
public void handleAndRethrow() throws IOException {
    try {
        processFile(null);
    } catch (IOException e) {
        System.out.println('Logging error before rethrow');
        throw e;  // re-throws the SAME exception object
    } catch (SQLException e) {
        // handled, not rethrown
    }
}

// Memory tip: 'throw' is a VERB (the action of throwing),
// 'throws' is a DECLARATION (a warning label on the method)

Keyword	किसके लिए	कहां	संख्या
throw	Exception instance actually throw करना	Method body के अंदर	एक exception per statement
throws	Method शायद exception throw करे बताना	Method signature में	Multiple, comma-separated

import java.io.IOException;
import java.sql.SQLException;

public void processFile(String path) throws IOException, SQLException {
    if (path == null) {
        throw new IllegalArgumentException('Path null नहीं हो सकता');
    }
}

public void caller() {
    try {
        processFile('data.txt');
    } catch (IOException | SQLException e) {
        System.out.println('Error: ' + e.getMessage());
    }
}

public void handleAndRethrow() throws IOException {
    try {
        processFile(null);
    } catch (IOException e) {
        System.out.println('Rethrow से पहले log करना');
        throw e;
    } catch (SQLException e) {
        // handled, rethrow नहीं
    }
}

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