Java: String to Integer Conversion

How do you convert a String to an Integer in Java?

Given the following String representation of a number

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String strNum = "123";

Here are two options for the conversion using Integer.parseInt or Integer.valueOf

Integer.parseInt

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int num = Integer.parseInt(strNum);
System.out.println(num);

or

Integer.valueOf

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Integer num = Integer.valueOf(strNum);
System.out.println(num);

Both examples produce the following output to the console:

Console Output

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123

Even though both programs print the same result to the console, there is a subtle difference. Notice that the first example returns a primitive int and the second example produces the Object Integer.