Assigning null to variable in finally block

This question already has an answer here:

Does finally always execute in Java? 50 answers

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Basically, what Java does is the following:

StringBuilder valueToReturn = builder.append("Passed!!!");
executeFinallyBlock();
return valueToReturn;

Whatever you're doing inside the finally block, Java has kept a reference to the value to return, and returns that reference. So it becomes:

StringBuilder valueToReturn = builder.append("Passed!!!");
builder = null;
return valueToReturn;

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The answer is simple.

Finally block will be executed for sure, since you are not returning any value from it, the try block returned value will be passed to original caller

try {
    builder.append("Test ");
    return builder.append("Passed!!!");
} finally {
    builder = null; 
}

Thus, you are getting "Test Passed!!!"

Changing the code to

StringBuilder builder = new StringBuilder();
try {
    builder.append("Test ");
    return builder.append("Passed!!!");
} finally {
    return null;
}

will certainly print "null" as you expected

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