20.16

java.lang.Runtime

THE PACKAGE JAVA.LANG

20.16.9

public void gc()

Calling this method suggests that the Java Virtual Machine expend effort toward

recycling discarded 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 a best effort to recycle all discarded objects. (The name

gc

 stands for  garbage collector. )

The Java runtime system will perform this recycling process automatically as

needed, in a separate thread, if the

gc

 method is not invoked explicitly.

See also the method

gc

 ( 20.18.12) of class

System

, which is the conven 

tional and convenient means of invoking this method.

20.16.10

public void runFinalization()

Calling this method suggests that the Java Virtual Machine expend effort toward

running the

finalize

 methods of objects that have been found to be discarded

but whose

finalize

 methods have not yet been run. When control returns from

the method call, the Java Virtual Machine has made a best effort to complete all

outstanding finalizations.

The Java runtime system will perform the finalization process automatically

as needed, in a separate thread, if the

runFinalization

 method is not invoked

explicitly.

See also the method

runFinalization

 ( 20.18.13) of class

System

, which is

the conventional and convenient means of invoking this method.

20.16.11

public void traceInstructions(boolean on)

Calling this method with argument

true

 suggests that the Java Virtual Machine

emit debugging information for every instruction it executes. The format of this

information, and the file or other output stream to which it is emitted, depends on

the host environment.

Calling this method with argument

false

 suggests that the Java Virtual

Machine cease emitting per instruction debugging information.

20.16.12

public void traceMethodCalls(boolean on)

Calling this method with argument

true

 suggests that the Java Virtual Machine

emit debugging information for every method call it executes. The format of this

information, and the file or other output stream to which it is emitted, depends on

the host environment.

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