AK created BCEL-172:
-----------------------
Summary: Searching bug
Key: BCEL-172
URL: https://issues.apache.org/jira/browse/BCEL-172
Project: Commons BCEL
Issue Type: Bug
Components: Main
Affects Versions: 5.2
Reporter: AK
It turned out that finder.search methods generates incorrect output.
For example:
finder.search("invokespecial")
Will find not only some INVOKESPECIAL opcodes but will return InstructionHandle
arrays in form:
[ invokespecial, nextOpCode]
So instead of returning x matching opcode(s) it returns x+1 matching opcodes in
one IntructionHandle array. This generates problem when invoking
finder.search("invokespecial return") which will throw
Exception in thread "main" java.lang.ArrayIndexOutOfBoundsException
at java.lang.System.arraycopy(Native Method)
at
org.apache.bcel.util.InstructionFinder.getMatch(InstructionFinder.java:171)
at
org.apache.bcel.util.InstructionFinder.search(InstructionFinder.java:231)
at
org.apache.bcel.util.InstructionFinder.search(InstructionFinder.java:250)
at Transform.transformMethod(Transform.java:66)
at Transform.main(Transform.java:25)
because of situation, that after return there is no more instruction(so
InstructionHandler too) to get. It occurs especially for deafult constructors
as they bytecode is like:
invokespecial
return.
Error exists because of errorneus instruction(line 230 in
InstructionFinder.java, method search()):
int lenExpr = (endExpr - startExpr) + 1;
There should be no "+1" part because:
int endExpr = matcher.end();
(which is one line above)
returns index AFTER match.
So bug generally(I didn't tested properly) could be repaired with replacing
errorneus line with:
int lenExpr = (endExpr - startExpr);
--
This message was sent by Atlassian JIRA
(v6.1#6144)
