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Open Menu /external/cddl/dtracetoolkit/dist/Examples/j_classflow_example.txt 
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Following are examples of j_classflow.d.  

This watches Java method entries and returns from all Java processes on the 
system with hotspot provider support (1.6.0) and the flag
"+ExtendedDTraceProbes".  eg, java -XX:+ExtendedDTraceProbes classfile

Here we can see it run on Code/Java/Func_abc. 

# j_classflow.d Func_abc
  C    PID TIME(us)         -- CLASS.METHOD
  0 311425 4789778117827    -> Func_abc.main
  0 311425 4789778117844      -> Func_abc.func_a
  0 311425 4789779120071        -> Func_abc.func_b
  0 311425 4789780130070          -> Func_abc.func_c
  0 311425 4789781140067          <- Func_abc.func_c
  0 311425 4789781140079        <- Func_abc.func_b
  0 311425 4789781140087      <- Func_abc.func_a
  0 311425 4789781140095    <- Func_abc.main
^C

The first column, C gives us the CPU ID.

The second column, TIME(us), gives us the time since boot in microseconds.

The third column, PID gives us the Process ID.

The fourth column, CLASS.METHOD gives us the Java class and method name.

We can see that Func_abc.main called Func.abc.func_a, which in turn
called Func_abc.funcb etc.

Here we can see an example of running it on java/io/BufferedOutputStream

# j_classflow.d java/io/BufferedOutputStream
  C    PID TIME(us)         -- CLASS.METHOD
  0 311461 4790094765413    -> java/io/BufferedOutputStream.<init>
  0 311461 4790094765459    <- java/io/BufferedOutputStream.<init>
  0 311461 4790094779559    -> java/io/BufferedOutputStream.<init>
  0 311461 4790094779595    <- java/io/BufferedOutputStream.<init>
  0 311461 4790094965883    -> java/io/BufferedOutputStream.write
  0 311461 4790094965913    <- java/io/BufferedOutputStream.write
  0 311461 4790094965926    -> java/io/BufferedOutputStream.flush
  0 311461 4790094965936      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966279      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966293    <- java/io/BufferedOutputStream.flush
  0 311461 4790094966588    -> java/io/BufferedOutputStream.write
  0 311461 4790094966602    <- java/io/BufferedOutputStream.write
  0 311461 4790094966610    -> java/io/BufferedOutputStream.flush
  0 311461 4790094966618      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966778      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966787    <- java/io/BufferedOutputStream.flush
  0 311461 4790094966811    -> java/io/BufferedOutputStream.flush
  0 311461 4790094966819      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966828      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790094966836    <- java/io/BufferedOutputStream.flush
  0 311461 4790095970345    -> java/io/BufferedOutputStream.write
  0 311461 4790095970372    <- java/io/BufferedOutputStream.write
  0 311461 4790095970382    -> java/io/BufferedOutputStream.flush
  0 311461 4790095970390      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970453      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970462    <- java/io/BufferedOutputStream.flush
  0 311461 4790095970737    -> java/io/BufferedOutputStream.write
  0 311461 4790095970751    <- java/io/BufferedOutputStream.write
  0 311461 4790095970759    -> java/io/BufferedOutputStream.flush
  0 311461 4790095970766      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970795      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970804    <- java/io/BufferedOutputStream.flush
  0 311461 4790095970828    -> java/io/BufferedOutputStream.flush
  0 311461 4790095970836      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970844      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790095970853    <- java/io/BufferedOutputStream.flush
  0 311461 4790096980348    -> java/io/BufferedOutputStream.write
  0 311461 4790096980373    <- java/io/BufferedOutputStream.write
  0 311461 4790096980383    -> java/io/BufferedOutputStream.flush
  0 311461 4790096980391      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980452      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980460    <- java/io/BufferedOutputStream.flush
  0 311461 4790096980735    -> java/io/BufferedOutputStream.write
  0 311461 4790096980749    <- java/io/BufferedOutputStream.write
  0 311461 4790096980757    -> java/io/BufferedOutputStream.flush
  0 311461 4790096980765      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980794      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980803    <- java/io/BufferedOutputStream.flush
  0 311461 4790096980826    -> java/io/BufferedOutputStream.flush
  0 311461 4790096980834      -> java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980843      <- java/io/BufferedOutputStream.flushBuffer
  0 311461 4790096980851    <- java/io/BufferedOutputStream.flush