Difficulty: Easy
Correct Answer: MyThread foo
Explanation:
Introduction / Context:This question combines constructor side effects with method overriding. The superclass MyThread prints in its constructor and defines two run methods: run() and an overloaded run(String). The anonymous subclass created in main overrides run().
Given Data / Assumptions:
Concept / Approach:Thread.start() always invokes the no-argument run() polymorphically. Overloads such as run(String) are not considered by the thread machinery. Therefore, after construction prints, the overridden run() in the anonymous class runs and prints " foo".
Step-by-Step Solution:
Create new MyThread() { public void run(){ System.out.println(" foo"); } } → constructor prints " MyThread".Call start() → JVM invokes overridden run() → prints " foo".No call to superclass run() or run(String) occurs.Verification / Alternative check:Replace println with print and observe spacing differences, but the token order remains MyThread then foo.
Why Other Options Are Wrong:
Common Pitfalls:Confusing overloading with overriding; Thread looks only for run().
Final Answer:MyThread foo
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