Finalize method

[silpa bathina]

Which of the following are true of the �finalize� method? Select all that apply:
A. It is a method on the base Object Class A
B. It cannot be overridden B
C. It is a static method C
D. It is called when an object is about to be garbage coll

[Dinuka Arsakularatne]

answer is D. it is called when an object is about to be collected for garbage collection. it ressurects the object from being garbage collected and the finalize method runs once. but after that if it becomes eligable for garabage collection again then it will check if the finalize method of that object has been run and if it has been run then it will not be run again and hence will be eligible for GC in the second time.

[Srinivas Kalvala]

Hello,

Look at the Java source for finalize() in Object class.

Still you have doubts, just shoot them out,

/**
     * Called by the garbage collector on an object when garbage collection
     * determines that there are no more references to the object.
     * A subclass overrides the <code>finalize</code> method to dispose of
     * system resources or to perform other cleanup. 
     * <p>
     * The general contract of <tt>finalize</tt> is that it is invoked 
     * if and when the Java<font size="-2"><sup>TM</sup></font> virtual 
     * machine has determined that there is no longer any
     * means by which this object can be accessed by any thread that has
     * not yet died, except as a result of an action taken by the
     * finalization of some other object or class which is ready to be
     * finalized. The <tt>finalize</tt> method may take any action, including
     * making this object available again to other threads; the usual purpose
     * of <tt>finalize</tt>, however, is to perform cleanup actions before 
     * the object is irrevocably discarded. For example, the finalize method 
     * for an object that represents an input/output connection might perform
     * explicit I/O transactions to break the connection before the object is
     * permanently discarded. 
     * <p>
     * The <tt>finalize</tt> method of class <tt>Object</tt> performs no 
     * special action; it simply returns normally. Subclasses of 
     * <tt>Object</tt> may override this definition.
     * <p>
     * The Java programming language does not guarantee which thread will 
     * invoke the <tt>finalize</tt> method for any given object. It is 
     * guaranteed, however, that the thread that invokes finalize will not 
     * be holding any user-visible synchronization locks when finalize is 
     * invoked. If an uncaught exception is thrown by the finalize method, 
     * the exception is ignored and finalization of that object terminates.
     * <p>
     * After the <tt>finalize</tt> method has been invoked for an object, no 
     * further action is taken until the Java virtual machine has again 
     * determined that there is no longer any means by which this object can 
     * be accessed by any thread that has not yet died, including possible
     * actions by other objects or classes which are ready to be finalized, 
     * at which point the object may be discarded.
     * <p>
     * The <tt>finalize</tt> method is never invoked more than once by a Java
     * virtual machine for any given object.
     * <p>
     * Any exception thrown by the <code>finalize</code> method causes 
     * the finalization of this object to be halted, but is otherwise 
     * ignored. 
     *
     * @throws Throwable the <code>Exception</code> raised by this method
     */
    [bold]protected void finalize() throws Throwable { }[/bold]