Name: kbR10066 Date: 04/10/2003


JCov agent may sometimes produce coverage files with
negative execution counters, which is obviously incorrect
behavor. Besides, such coverage files confuse other JCov
utilities.

To reproduce:

1. Compile the following source (a.java):
% <JDK14>/bin/javac a.java

--- a.java ---
public class a {
public static void main(String[] args) {
System.out.println("Hello world!");
}
}
--- end of a.java ---

2. Create the following coverage file (java.jcov) in current directory:

--- java.jcov ---
JCOV-DATA-FILE-VERSION: 2.0
CLASS: a [public]
SRCFILE: a.java
TIMESTAMP: 0
DATA: M
#kind line position count
METHOD: <init>()V [public]
1 1 0 0
METHOD: main([Ljava/lang/String;)V [public static]
1 3 0 2147483648
--- end of java.jcov ---

3. Run class a under -Xrunjcov:
% <JDK14>/bin/java -Xrunjcov:t=m -cp . a

The following coverage file will be produced (java.jcov):

--- java.jcov ---
JCOV-DATA-FILE-VERSION: 2.0
CLASS: a [public]
SRCFILE: a.java
TIMESTAMP: 0
DATA: M
#kind line position count
METHOD: <init>()V [public]
1 1 0 0
METHOD: main([Ljava/lang/String;)V [public static]
1 3 0 -2147483647
--- end of java.jcov ---

Note the '-2147483647' execution counter.
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