src/java.base/share/classes/java/lang/Runtime.java

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 713     }
 714 
 715     /**
 716      * Enables/Disables tracing of instructions.
 717      * If the <code>boolean</code> argument is <code>true</code>, this
 718      * method suggests that the Java virtual machine emit debugging
 719      * information for each instruction in the virtual machine as it
 720      * is executed. The format of this information, and the file or other
 721      * output stream to which it is emitted, depends on the host environment.
 722      * The virtual machine may ignore this request if it does not support
 723      * this feature. The destination of the trace output is system
 724      * dependent.
 725      * <p>
 726      * If the <code>boolean</code> argument is <code>false</code>, this
 727      * method causes the virtual machine to stop performing the
 728      * detailed instruction trace it is performing.
 729      *
 730      * @param   on   <code>true</code> to enable instruction tracing;
 731      *               <code>false</code> to disable this feature.
 732      */
 733     public native void traceInstructions(boolean on);
 734 
 735     /**
 736      * Enables/Disables tracing of method calls.
 737      * If the <code>boolean</code> argument is <code>true</code>, this
 738      * method suggests that the Java virtual machine emit debugging
 739      * information for each method in the virtual machine as it is
 740      * called. The format of this information, and the file or other output
 741      * stream to which it is emitted, depends on the host environment. The
 742      * virtual machine may ignore this request if it does not support
 743      * this feature.
 744      * <p>
 745      * Calling this method with argument false suggests that the
 746      * virtual machine cease emitting per-call debugging information.
 747      *
 748      * @param   on   <code>true</code> to enable instruction tracing;
 749      *               <code>false</code> to disable this feature.
 750      */
 751     public native void traceMethodCalls(boolean on);
 752 
 753     /**
 754      * Loads the native library specified by the filename argument.  The filename
 755      * argument must be an absolute path name.
 756      * (for example
 757      * <code>Runtime.getRuntime().load("/home/avh/lib/libX11.so");</code>).
 758      *
 759      * If the filename argument, when stripped of any platform-specific library
 760      * prefix, path, and file extension, indicates a library whose name is,
 761      * for example, L, and a native library called L is statically linked
 762      * with the VM, then the JNI_OnLoad_L function exported by the library
 763      * is invoked rather than attempting to load a dynamic library.
 764      * A filename matching the argument does not have to exist in the file
 765      * system. See the JNI Specification for more details.
 766      *
 767      * Otherwise, the filename argument is mapped to a native library image in
 768      * an implementation-dependent manner.
 769      * <p>
 770      * First, if there is a security manager, its <code>checkLink</code>
 771      * method is called with the <code>filename</code> as its argument.




 713     }
 714 
 715     /**
 716      * Enables/Disables tracing of instructions.
 717      * If the <code>boolean</code> argument is <code>true</code>, this
 718      * method suggests that the Java virtual machine emit debugging
 719      * information for each instruction in the virtual machine as it
 720      * is executed. The format of this information, and the file or other
 721      * output stream to which it is emitted, depends on the host environment.
 722      * The virtual machine may ignore this request if it does not support
 723      * this feature. The destination of the trace output is system
 724      * dependent.
 725      * <p>
 726      * If the <code>boolean</code> argument is <code>false</code>, this
 727      * method causes the virtual machine to stop performing the
 728      * detailed instruction trace it is performing.
 729      *
 730      * @param   on   <code>true</code> to enable instruction tracing;
 731      *               <code>false</code> to disable this feature.
 732      */
 733     public void traceInstructions(boolean on) { }
 734 
 735     /**
 736      * Enables/Disables tracing of method calls.
 737      * If the <code>boolean</code> argument is <code>true</code>, this
 738      * method suggests that the Java virtual machine emit debugging
 739      * information for each method in the virtual machine as it is
 740      * called. The format of this information, and the file or other output
 741      * stream to which it is emitted, depends on the host environment. The
 742      * virtual machine may ignore this request if it does not support
 743      * this feature.
 744      * <p>
 745      * Calling this method with argument false suggests that the
 746      * virtual machine cease emitting per-call debugging information.
 747      *
 748      * @param   on   <code>true</code> to enable instruction tracing;
 749      *               <code>false</code> to disable this feature.
 750      */
 751     public void traceMethodCalls(boolean on) { }
 752 
 753     /**
 754      * Loads the native library specified by the filename argument.  The filename
 755      * argument must be an absolute path name.
 756      * (for example
 757      * <code>Runtime.getRuntime().load("/home/avh/lib/libX11.so");</code>).
 758      *
 759      * If the filename argument, when stripped of any platform-specific library
 760      * prefix, path, and file extension, indicates a library whose name is,
 761      * for example, L, and a native library called L is statically linked
 762      * with the VM, then the JNI_OnLoad_L function exported by the library
 763      * is invoked rather than attempting to load a dynamic library.
 764      * A filename matching the argument does not have to exist in the file
 765      * system. See the JNI Specification for more details.
 766      *
 767      * Otherwise, the filename argument is mapped to a native library image in
 768      * an implementation-dependent manner.
 769      * <p>
 770      * First, if there is a security manager, its <code>checkLink</code>
 771      * method is called with the <code>filename</code> as its argument.