Name: swC45995 Date: 10/07/96


The verifier catches an assignment to a nonextisting array component before
execution and by doing so prevents the subsequent execution. This takes place
only for arrays of reference types. For example, of the following test

public class test
{
public static void main(String argv[])
{
test [] a = null, b;

b = a;
b[0] = new test();
}
}

with the -verify option produces verifier diagnostics:

novo40% java -verify test
VERIFIER ERROR test.main([Ljava/lang/String;)V:
Incompatible types for storing into array of arrays or objects
Can't find class test

while its execution without this option produces the right output:

novo40% java test
java.lang.NullPointerException
at test.main(test.java:8)

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