The JavaTM Tutorial

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Trail: Essential Java Classes
Lesson: Using String and StringBuffer

## Converting Objects to Strings

### The `toString` Method

> It's often convenient or necessary to convert an object to a `String` because you need to pass it to a method that accepts only `String` values. The `reverseIt` method used earlier in this lesson uses `StringBuffer`'s `toString` method to convert the `StringBuffer` to a `String` object before returning the `String`.

> >     class ReverseString {
> >         public static String reverseIt(String source) {
> >             int i, len = source.length();
> >             StringBuffer dest = new StringBuffer(len);

> >             for (i = (len - 1); i >= 0; i--) {
> >                 dest.append(source.charAt(i));
> >             }
> >             return dest.toString();
> >         }
> >     }

> All classes inherit `toString` from the `Object` class and many classes in the `java.lang` package override this method to provide an implementation that is meaningful to that class. For example, the "type wrapper" classes--`Character`, `Integer`, `Boolean`, and the others--all override `toString` to provide a `String` representation of the object.

### The valueOf Method

> As a convenience, the `String` class provides the class method `valueOf`, You can use `valueOf` to convert variables of different types to `String`s. For example, to print the value of pi:

> >     System.out.println(String.valueOf(Math.PI));

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