Which class should you use to obtain design information about an object?

Java Interview Questions and Answers (part 2)

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268. Which class should you use to obtain design information about an object?

The Class class is used to obtain information about an object's design.

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Other Interview Questions

• Which java.util classes and interfaces support event handling?
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• What are wrapper classes?
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• Can an object's finalize() method be invoked while it is reachable?
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• What value does readLine() return when it has reached the end of a file?
• What is the immediate superclass of the Dialog class?
• What is clipping?
• What is a native method?
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• What is the range of the char type?
• In which package are most of the AWT events that support the event-delegation model defined?
• What is the immediate superclass of Menu?
• What is the purpose of finalization?
• Which class is the immediate superclass of the MenuComponent class.
• What invokes a thread's run() method?
• What is the difference between the Boolean & operator and the && operator?
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• What is the GregorianCalendar class?
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• What is the purpose of the Runtime class?
• How many times may an object's finalize() method be invoked by the garbage collector?
• What is the purpose of the finally clause of a try-catch-finally statement? garbage collector?
• What is the argument type of a program's main() method?
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• What is the Locale class?
• Can a double value be cast to a byte?
• What is the difference between a break statement and a continue statement?
• What must a class do to implement an interface?
• What method is invoked to cause an object to begin executing as a separate thread?
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• What is the advantage of the event-delegation model over the earlier event-inheritance model?
• Which containers may have a MenuBar?
• How are commas used in the initialization and iteration parts of a for statement?
• What is the purpose of the wait(), notify(), and notifyAll() methods?
• What is an abstract method?
• How are Java source code files named?
• What is the relationship between the Canvas class and the Graphics class?
• What are the high-level thread states?
• What value does read() return when it has reached the end of a file?
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• What is the difference between a static and a non-static inner class?
• What is the difference between the String and StringBuffer classes?
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• What is an object's lock and which objects have locks?
• What is the Dictionary class?
• How are the elements of a BorderLayout organized?
• What is the % operator?
• When can an object reference be cast to an interface reference?
• What is the difference between a Window and a Frame?
• Which class is extended by all other classes?
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• Which TextComponent method is used to set a TextComponent to the read-only state?
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• Which class should you use to obtain design information about an object?
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• What modifiers may be used with an interface declaration?
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• What is the difference between a while statement and a do statement?
• How are the elements of a GridBagLayout organized?
• What advantage do Java's layout managers provide over traditional windowing systems?
• What is the Collection interface?
• What modifiers can be used with a local inner class?
• What is the difference between static and non-static variables?
• What is the difference between the paint() and repaint() methods?
• What is the purpose of the File class?
• Can an exception be rethrown?
• Which Math method is used to calculate the absolute value of a number?
• How does multithreading take place on a computer with a single CPU?
• When does the compiler supply a default constructor for a class?
• When is the finally clause of a try-catch-finally statement executed?
• Which class is the immediate superclass of the Container class?
• If a method is declared as protected, where may the method be accessed?
• How can the Checkbox class be used to create a radio button?
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• What restrictions are placed on method overloading?
• What happens when you invoke a thread's interrupt method while it is sleeping or waiting?
• What is casting?
• What is the return type of a program's main() method?
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• What is the difference between a Choice and a List?
• What class of exceptions are generated by the Java run-time system?
• What class allows you to read objects directly from a stream?
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• Under what conditions is an object's finalize() method invoked by the garbage collector?
• How are this () and super () used with constructors?
• What is the relationship between a method's throws clause and the exceptions that can be thrown during the method's execution?
• What is the difference between the JDK 1.02 event model and the event-delegation model introduced with JDK 1.1?
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• Why are the methods of the Math class static?
• What Checkbox method allows you to tell if a Checkbox is checked?
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• How are the elements of a GridLayout organized?
• What an I/O filter?
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• Are true and false keywords?
• What is a void return type?
• What is the purpose of the enableEvents() method?
• What is the difference between the File and RandomAccessFile classes?
• What happens when you add a double value to a String?
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• What is the purpose of garbage collection?
• What is a compilation unit?
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