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6.10 The return Statement

A return statement returns control of the current method or constructor to the caller:

[Graphic: Figure from the text]

If a return statement does not contain an expression, the statement must be in a method declared with the void return type or in a constructor. Otherwise, the compiler issues an error message. When a return statement does not contain an expression, the statement simply attempts to transfer control back to the method or constructor that invoked the current method or constructor.

If a return statement contains an expression, it must be in a method that returns a value or the compiler issues an error message. The type of the expression must be assignment-compatible with the declared return type of the method. The return statement attempts to transfer control back to the method or constructor that invoked the current method. The value produced by the expression is the return value of the current method.

Here's an example of a return statement:

int doubleIt (int k) {
    return k*2;
}

If a return statement occurs inside a try statement, control may not immediately transfer to the invoking method or constructor. If a try statement has a finally clause, the finally block is executed before control leaves the try statement for any reason. This means that if a return statement occurs inside a try statement (but not in its finally block), the finally block is executed first, before the control transfer can take place.

If the finally block contains a break, continue, return, or throw statement, the pending control transfer for the previously executed return statement is forgotten. Instead, control is transferred to the target of the break, continue, return, or throw statement in the finally block.

If the finally block does not contain a break, continue, return, or throw statement, the pending control transfer happens after the finally block is done executing, unless there is another enclosing try statement. If there is such a try statement and it has a finally clause, that finally block is also executed before the control transfer can take place. Execution proceeds in this manner until control is transferred to the invoking method or constructor.

References Constructors; Expression 4; Identifiers; Methods; The break Statement; The continue Statement; The throw Statement; The try Statement


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