Throw try catch finally in compiling

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Throw an exception positively

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void noZero(int i) throws Exception {
	if(i == 0)
		throw new Exception("no zero");
}

javap

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void noZero(int) throws java.lang.Exception;
    Code:
       0: iload_1
       1: ifne          14
       // class java/lang/Exception
       4: new           #2
       7: dup
       // String no zero
       8: ldc           #3
       // Method java/lang/Exception.
       //"<init>":(Ljava/lang/String;)V
      10: invokespecial #4
      13: athrow
      14: return

  1. if not equals pass the throw part
  2. if equals take constant string as param create a Exception.
  3. throw it to the caller[handler?].

Catch an exception

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void e() {
	try {
    noZero(0);
  } catch(ExcpA a) {}
	catch(ExcpB b) {}
	catch(Exception e) {}
}

javap

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void e();
    Code:
       0: aload_0
       1: iconst_0
       // Method noZero:(I)V
       2: invokevirtual #5
       5: goto          17
       8: astore_1
       9: goto          17
      12: astore_1
      13: goto          17
      16: astore_1
      17: return
    Exception table:
       from    to  target type
           0     5     8   Class HaveATry$ExcpA
           0     5    12   Class HaveATry$ExcpB
           0     5    16   Class java/lang/Exception

excption table
Every catcher have a chance to catch.

astore_1
Beginning of handler for excpSentry() store thrown value in local var 1.

Finally

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int f() {
	try { noZero(0); }
	catch(Exception e) {
		return 1;
	}
	finally {
		return 2;
	}
}

javap

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int f();
    Code:
       0: aload_0
       1: iconst_0
       // Method noZero:(I)V
       2: invokevirtual #5
       5: iconst_2
       6: ireturn
       7: astore_1
       8: iconst_1
       9: istore_2
      10: iconst_2
      11: ireturn
      12: astore_3
      13: iconst_2
      14: ireturn
    Exception table:
       from    to  target type
           0     5     7   Class java/lang/Exception
           0     5    12   any
           7    10    12   any

5/6 copy instructions of 13/14.
7th is the Exception handler.
11th can’t reach.
what’s the object of istore_2/ istore_3 ???

istore_2 the catcher itself’s handler?
istore_3 the finaly’s handler comes from istore_2 ?

any mean in range instructions finished then goto target.

The final return handle by finally got 2