java convert string to long

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// solution 1
long num1 = Long.parseLong("123"); // 123

// solution 2
Long num2 = Long.valueOf("123"); // 123

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public class Example {

    public static void main(String[] args) {
        String str = "123";
        long num = Long.parseLong(str);
        System.out.println(num); // 123
    }
}

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public class Example {

    public static void main(String[] args) {
        String str = "123";
        Long num = Long.valueOf(str);
        System.out.println(num); // 123
    }
}

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public class Example {

    public static void main(String[] args) {

        // Long.parseLong() - returns long
        System.out.println(Long.parseLong("123")); // 123
        System.out.println(Long.parseLong("+123")); // 123
        System.out.println(Long.parseLong("-123")); // -123

        // Long.valueOf() - returns Long
        System.out.println(Long.valueOf("123")); // 123
        System.out.println(Long.valueOf("+123")); // 123
        System.out.println(Long.valueOf("-123")); // -123
    }
}

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public class Example {

    public static void main(String[] args) {
        String str = "123a";
        long num = Long.parseLong(str);
        System.out.println(num);
    }
}