The exception occures when trying to run a non-existing sig file.

/java/jct-tools/users1/shoushan/SigTest1.3/sigtest-1.3/lib/sigtestdev.jar

>>> Setup in static mode
Class path: "./classes:/java/re/jdk/1.5.0/archive/fcs/binaries/solaris-sparcv9/jre/lib/rt.jar"
Constant checking : on
Found in total: 13086 classes
Selected by -Package: 3 classes
Written to sigfile: 1 classes (and 2 inner classes)
STATUS:Passed.

>>> SignatureTest in static mode
Exception in thread "main" java.lang.NullPointerException
        at com.sun.tdk.signaturetest.SignatureTest.check(SignatureTest.java:553)
        at com.sun.tdk.signaturetest.SignatureTest.run(SignatureTest.java:231)
        at com.sun.tdk.signaturetest.SignatureTest.main(SignatureTest.java:201)

Run the following script to reprodcue the problem:
#!/bin/sh

SGT=/java/jct-tools/users1/shoushan/SigTest1.3/sigtest-1.3/lib/sigtestdev.jar
JH=/java/re/jdk/1.5.0/archive/fcs/binaries/solaris-sparcv9
PKG=api

$JH/bin/javac -d classes Paint.java

    echo "\n>>> Setup in static mode"
    $JH/bin/java -cp $SGT \
      com.sun.tdk.signaturetest.Setup \
       -static \
       -package $PKG \
       -classpath ./classes:$JH/jre/lib/rt.jar \
       -filename ./s.sig
   

  # static mode
    echo "\n>>> SignatureTest in static mode"

    $JH/bin/java -cp $SGT \
      com.sun.tdk.signaturetest.SignatureTest \
       -static \
       -package $PKG \
       -classpath ./classes:$JH/jre/lib/rt.jar \
       -filename ./s1.sig