THE PACKAGE JAVA.LANG

java.lang.Runtime

20.16

20.16.5

public Process exec(String cmdarray[])

throws IOException, SecurityException,

NullPointerException, IndexOutOfBoundsException

The command specified by the tokens in

cmdarray

 is executed as a command in a

separate process.

This method behaves exactly as if it performs the call:

exec(cmdarray, null)

See  20.16.6.

20.16.6

public Process exec(String cmdarray[], String envp[])

throws IOException, SecurityException,

NullPointerException, IndexOutOfBoundsException

First, if there is a security manager, its

checkExec

 method ( 20.17.14) is called

with the first component of the array

cmdarray

 as its argument.

If

cmdarray

 is

null

, a

NullPointerException

 is thrown. If

cmdarray

 is an

empty array (has length

0

), an

IndexOutOfBoundsException

 is thrown.

Given an array of strings

cmdarray

, representing the tokens of a command

line, and an array of strings

envp

, representing an  environment  that defines sys 

tem properties, this method creates a new process in which to execute the speci 

fied command and returns a

Process

 object ( 20.15) representing the new

process.

20.16.7

public long totalMemory()

The total amount of memory currently available for current and future created

objects, measured in bytes, is returned. 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.

20.16.8

public long freeMemory()

An approximation to the total amount of memory currently available for future

created objects, measured in bytes, is returned. This value is always less than the

current value returned by the

totalMemory

 method. Calling the

gc

 method may

increase the value returned by

freeMemory

.

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