runtime.html

API資料大全

<P>
<DD>Enable or disable finalization on exit; doing so specifies that the
 finalizers of all objects that have finalizers that have not yet been
 automatically invoked are to be run before the Java runtime exits.
 By default, finalization on exit is disabled.
 
 <p>If there is a security manager, 
 its <code>checkExit</code> method is first called
 with 0 as its argument to ensure the exit is allowed. 
 This could result in a SecurityException.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>value</CODE> - true to enable finalization on exit, false to disable<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its <code>checkExit</code> 
        method doesn't allow the exit.<DT><B>Since: </B><DD>JDK1.1</DD>
<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exit(int)"><CODE>exit(int)</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#gc()"><CODE>gc()</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExit(int)"><CODE>SecurityManager.checkExit(int)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String)"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>&nbsp;command)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified string command in a separate process. 
 <p>
 The <code>command</code> argument is parsed into tokens and then 
 executed as a command in a separate process. The token parsing is 
 done by a <A HREF="../../java/util/StringTokenizer.html"><CODE>StringTokenizer</CODE></A> created by the call:
 <blockquote><pre>
 new StringTokenizer(command)
 </pre></blockquote> 
 with no further modifications of the character categories. 
 This method has exactly the same effect as 
 <code>exec(command, null)</code>.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>command</CODE> - a specified system command.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a subprocess.<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exec(java.lang.String, java.lang.String[])"><CODE>exec(java.lang.String, java.lang.String[])</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String, java.lang.String[])"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>&nbsp;cmd,
                    <A HREF="../../java/lang/String.html">String</A>[]&nbsp;envp)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified string command in a separate process with the 
 specified environment. 
 <p>
 This method breaks the <code>command</code> string into tokens and 
 creates a new array <code>cmdarray</code> containing the tokens in the 
 order that they were produced by the string tokenizer; it 
 then performs the call <code>exec(cmdarray, envp)</code>. The token
 parsing is done by a <A HREF="../../java/util/StringTokenizer.html"><CODE>StringTokenizer</CODE></A> created by 
 the call: 
 <blockquote><pre>
 new StringTokenizer(command)
 </pre></blockquote>
 with no further modification of the character categories. 

 <p>
 The environment variable settings are specified by <tt>envp</tt>.
 If <tt>envp</tt> is <tt>null</tt>, the subprocess inherits the 
 environment settings of the current process.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>cmd</CODE> - a specified system command.<DD><CODE>envp</CODE> - array of strings, each element of which 
                       has environment variable settings in format
                       <i>name</i>=<i>value</i>.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a subprocess.<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exec(java.lang.String[])"><CODE>exec(java.lang.String[])</CODE></A>, 
<A HREF="../../java/lang/Runtime.html#exec(java.lang.String[], java.lang.String[])"><CODE>exec(java.lang.String[], java.lang.String[])</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String, java.lang.String[], java.io.File)"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>&nbsp;command,
                    <A HREF="../../java/lang/String.html">String</A>[]&nbsp;envp,
                    <A HREF="../../java/io/File.html">File</A>&nbsp;dir)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified string command in a separate process with the
 specified environment and working directory. 
 <p>
 This method breaks the <code>command</code> string into tokens and 
 creates a new array <code>cmdarray</code> containing the tokens in the 
 order that they were produced by the string tokenizer; it 
 then performs the call <code>exec(cmdarray, envp)</code>. The token
 parsing is done by a <A HREF="../../java/util/StringTokenizer.html"><CODE>StringTokenizer</CODE></A> created by 
 the call: 
 <blockquote><pre>
 new StringTokenizer(command)
 </pre></blockquote>
 with no further modification of the character categories. 

 <p>
 The environment variable settings are specified by <tt>envp</tt>.
 If <tt>envp</tt> is <tt>null</tt>, the subprocess inherits the 
 environment settings of the current process.

 <p>
 The working directory of the new subprocess is specified by <tt>dir</tt>.
 If <tt>dir</tt> is <tt>null</tt>, the subprocess inherits the 
 current working directory of the current process.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>command</CODE> - a specified system command.<DD><CODE>envp</CODE> - array of strings, each element of which 
                       has environment variable settings in format
                       <i>name</i>=<i>value</i>.<DD><CODE>dir</CODE> - the working directory of the subprocess, or
                       <tt>null</tt> if the subprocess should inherit
                       the working directory of the current process.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a subprocess.<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exec(java.lang.String[], java.lang.String[], java.io.File)"><CODE>exec(java.lang.String[], java.lang.String[], File)</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String[])"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>[]&nbsp;cmdarray)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified command and arguments in a separate process.
 <p>
 The command specified by the tokens in <code>cmdarray</code> is 
 executed as a command in a separate process. This has exactly the 
 same effect as <code>exec(cmdarray, null)</code>. 
 <p>
 If there is a security manager, its <code>checkExec</code> 
 method is called with the first component of the array 
 <code>cmdarray</code> as its argument. This may result in a security 
 exception.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>cmdarray</CODE> - array containing the command to call and
                        its arguments.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a subprocess.<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs<DT><B>See Also: </B><DD><A HREF="../../java/lang/Runtime.html#exec(java.lang.String[], java.lang.String[])"><CODE>exec(java.lang.String[], java.lang.String[])</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String[], java.lang.String[])"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>[]&nbsp;cmdarray,
                    <A HREF="../../java/lang/String.html">String</A>[]&nbsp;envp)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified command and arguments in a separate process
 with the specified environment. 
 <p>
 Given an array of strings <code>cmdarray</code>, representing the 
 tokens of a command line, and an array of strings <code>envp</code>, 
 representing "environment" variable settings, this method creates 
 a new process in which to execute the specified command. 

 <p>
 If <tt>envp</tt> is <tt>null</tt>, the subprocess inherits the 
 environment settings of the current process.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>cmdarray</CODE> - array containing the command to call and
                        its arguments.<DD><CODE>envp</CODE> - array of strings, each element of which 
                        has environment variable settings in format
                        <i>name</i>=<i>value</i>.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a subprocess.<DD><CODE><A HREF="../../java/lang/NullPointerException.html">NullPointerException</A></CODE> - if <code>cmdarray</code> is 
             <code>null</code>.<DD><CODE><A HREF="../../java/lang/IndexOutOfBoundsException.html">IndexOutOfBoundsException</A></CODE> - if <code>cmdarray</code> is an 
             empty array (has length <code>0</code>).<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs<DT><B>See Also: </B><DD><A HREF="../../java/lang/Process.html"><CODE>Process</CODE></A>, 
<A HREF="../../java/lang/SecurityException.html"><CODE>SecurityException</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="exec(java.lang.String[], java.lang.String[], java.io.File)"><!-- --></A><H3>
exec</H3>
<PRE>
public <A HREF="../../java/lang/Process.html">Process</A> <B>exec</B>(<A HREF="../../java/lang/String.html">String</A>[]&nbsp;cmdarray,
                    <A HREF="../../java/lang/String.html">String</A>[]&nbsp;envp,
                    <A HREF="../../java/io/File.html">File</A>&nbsp;dir)
             throws <A HREF="../../java/io/IOException.html">IOException</A></PRE>
<DL>
<DD>Executes the specified command and arguments in a separate process with
 the specified environment and working directory. 
 <p>
 If there is a security manager, its <code>checkExec</code> 
 method is called with the first component of the array 
 <code>cmdarray</code> as its argument. This may result in a security 
 exception. 
 <p>
 Given an array of strings <code>cmdarray</code>, representing the 
 tokens of a command line, and an array of strings <code>envp</code>, 
 representing "environment" variable settings, this method creates 
 a new process in which to execute the specified command. 

 <p>
 If <tt>envp</tt> is <tt>null</tt>, the subprocess inherits the 
 environment settings of the current process.

 <p>
 The working directory of the new subprocess is specified by <tt>dir</tt>.
 If <tt>dir</tt> is <tt>null</tt>, the subprocess inherits the 
 current working directory of the current process.<DD><DL>
<DT><B>Parameters:</B><DD><CODE>cmdarray</CODE> - array containing the command to call and
                        its arguments.<DD><CODE>envp</CODE> - array of strings, each element of which 
                        has environment variable settings in format
                        <i>name</i>=<i>value</i>.<DD><CODE>dir</CODE> - the working directory of the subprocess, or
                        <tt>null</tt> if the subprocess should inherit
                        the working directory of the current process.<DT><B>Returns:</B><DD>a <code>Process</code> object for managing the subprocess.<DT><B>Throws:</B><DD><CODE><A HREF="../../java/lang/SecurityException.html">SecurityException</A></CODE> - if a security manager exists and its  
             <code>checkExec</code> method doesn't allow creation of a 
             subprocess.<DD><CODE><A HREF="../../java/lang/NullPointerException.html">NullPointerException</A></CODE> - if <code>cmdarray</code> is 
             <code>null</code>.<DD><CODE><A HREF="../../java/lang/IndexOutOfBoundsException.html">IndexOutOfBoundsException</A></CODE> - if <code>cmdarray</code> is an 
             empty array (has length <code>0</code>).<DD><CODE><A HREF="../../java/io/IOException.html">IOException</A></CODE> - if an I/O error occurs.<DT><B>See Also: </B><DD><A HREF="../../java/lang/Process.html"><CODE>Process</CODE></A>, 
<A HREF="../../java/lang/SecurityException.html"><CODE>SecurityException</CODE></A>, 
<A HREF="../../java/lang/SecurityManager.html#checkExec(java.lang.String)"><CODE>SecurityManager.checkExec(java.lang.String)</CODE></A></DL>
</DD>
</DL>
<HR>

<A NAME="freeMemory()"><!-- --></A><H3>
freeMemory</H3>
<PRE>
public long <B>freeMemory</B>()</PRE>
<DL>
<DD>Returns the amount of free memory in the system. Calling the 
 <code>gc</code> method may result in increasing the value returned 
 by <code>freeMemory.</code><DD><DL>
<DT><B>Returns:</B><DD>an approximation to the total amount of memory currently
          available for future allocated objects, measured in bytes.</DL>
</DD>
</DL>
<HR>

<A NAME="totalMemory()"><!-- --></A><H3>
totalMemory</H3>
<PRE>
public long <B>totalMemory</B>()</PRE>
<DL>
<DD>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.
 <p>
 Note that the amount of memory required to hold an object of any 
 given type may be implementation-dependent.<DD><DL>
<DT><B>Returns:</B><DD>the total amount of memory currently available for current 
          and future objects, measured in bytes.</DL>
</DD>
</DL>
<HR>

<A NAME="gc()"><!-- --></A><H3>
gc</H3>
<PRE>
public void <B>gc</B>()</PRE>
<DL>