FileDocCategorySizeDatePackage
Runtime.javaAPI DocJ2ME MIDP 2.03677Thu Nov 07 12:02:26 GMT 2002java.lang

Runtime

public class Runtime extends Object
Every Java application has a single instance of class Runtime that allows the application to interface with the environment in which the application is running. The current runtime can be obtained from the getRuntime method.

An application cannot create its own instance of this class.

author
unascribed
version
1.53, 12/04/99 (CLDC 1.0, Spring 2000)
see
java.lang.Runtime#getRuntime()
since
JDK1.0

Fields Summary
private static Runtime
currentRuntime
Constructors Summary
private Runtime()
Don't let anyone else instantiate this class

Methods Summary
public voidexit(int status)
Terminates the currently running Java application. This method never returns normally.

The argument serves as a status code; by convention, a nonzero status code indicates abnormal termination.

param
status exit status.
since
JDK1.0

        /*
         * Since we have no way of telling if this method is being called by
         * a MIDlet, assume we are being called from a MIDlet and throw a
         * SecurityException
         */
	throw new SecurityException(
            "MIDP lifecycle does not support system exit.");
    
public native longfreeMemory()
Returns the amount of free memory in the system. Calling the gc method may result in increasing the value returned by freeMemory.

return
an approximation to the total amount of memory currently available for future allocated objects, measured in bytes.

public native voidgc()
Runs the garbage collector. Calling this method suggests that the Java Virtual Machine expend effort toward recycling unused objects in order to make the memory they currently occupy available for quick reuse. When control returns from the method call, the Java Virtual Machine has made its best effort to recycle all discarded objects.

The name gc stands for "garbage collector". The Java Virtual Machine performs this recycling process automatically as needed, in a separate thread, even if the gc method is not invoked explicitly.

The method {@link System#gc()} is hte conventional and convenient means of invoking this method.

public static java.lang.RuntimegetRuntime()
Returns the runtime object associated with the current Java application. Most of the methods of class Runtime are instance methods and must be invoked with respect to the current runtime object.

return
the Runtime object associated with the current Java application.


                                                               
         
        return currentRuntime;
    
public native longtotalMemory()
Returns the total amount of memory in the Java Virtual Machine. The value returned by this method may vary over time, depending on the host environment.

Note that the amount of memory required to hold an object of any given type may be implementation-dependent.

return
the total amount of memory currently available for current and future objects, measured in bytes.