Tip Bank

Question: I need to extend class A which resides in a different package, butclass A has only one constructor which is package protected. I get a compile error in class

Question: Is there a significant speed advantage to using Hashtables over Vectors? Answer: The answer depends on how you are using those containers classes. Ifyou are only using them for

Question: I have been looking everywhere for information on HashMaps,particularly how to put one hash map into another HashMap. Answer: This is where the expression RTFM (Read That Fine Manual)

Question: How do you stop a Thread without using the stop() method? Answer: The recommended method for stopping threads in Java is for each thread topoll a boolean value or

Question: I have written an applet which uses a Graphics object to draw movingcircles. However, when multiple threads accesses the same Graphics object,the circles disappear after being on screen for

When you are inserting data into Oracle tables in SQL*Plus using hard-coded string, some of the character fields may contain the ampersand character (&). The following is an example: insert

Although an index is not mandatory on your foreign keys, if they are not indexed you will cause additional locking when certain Data Manipulation Language statements are executed against the

Many programmers create stored procedures out of large bodies of database trigger codes. This has primarily been because while stored procedures are stored in compiled form, database triggers are compiled

In a PL/SQL block, if you are querying a database table, you need to declare data variables to hold column values returned from the query. The variables can be declared