Java syntax
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doSomethingWithObject(obj);
}
Thread concurrency control
Java has built-in tools for multi-thread programming. For the purposes of thread synchronization the synchronized statement is included in Java language.
To make a code block synchronized, it is preceded by the synchronized keyword followed by the lock object inside the brackets. When the executing thread reaches the synchronized block, it acquires a mutual exclusion lock, executes the block, then releases the lock. No threads may enter this block until the lock is released. Any non-null reference type may be used as the lock.
/* Acquires lock on someObject. It must be of
a reference type and must be non-null */
synchronized (someObject) {
// Synchronized statements
}
assert statement
assert statements have been available since J2SE 1.4. These types of statements are used to make assertions in the source code, which can be turned on and off during execution for specific classes or packages. To declare an assertion the assert keyword is used followed by a conditional expression. If it evaluates to false when the statement is executed, an exception is thrown. This statement can include a colon followed by another expression, which will act as the exception's detail message.
// If n equals 0, AssertionError is thrown
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