Java syntax
part 17/46 · 86.7 KB total
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return statement ends execution immediately, except for one case: if the statement is encountered within a try block and it is complemented by a finally, control is passed to the finally block.
void doSomething(boolean streamClosed) {
try {
if (streamClosed) {
return;
}
readFromStream();
} finally {
/* Will be called last even if
readFromStream() was not called */
freeResources();
}
}
Exception handling statements
try-catch-finally statements
Exceptions are managed within try ... catch blocks.
try {
// Statements that may throw exceptions
methodThrowingExceptions();
} catch (Exception ex) {
// Exception caught and handled here
reportException(ex);
} finally {
// Statements always executed after the try/catch blocks
freeResources();
}
The statements within the try block are executed, and if any of them throws an exception, execution of the block is discontinued and the exception is handled by the catch block. There may be multiple catch blocks, in which case the first block with an exception variable whose type matches the type of the thrown exception is executed.
Java SE 7 also introduced multi-catch clauses besides uni-catch clauses. This type of catch clauses allows Java to handle different types of exceptions in a single block provided they are not subclasses of each other.
try {
methodThrowingExceptions();
} catch (IOException | IllegalArgumentException ex) {
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