Unit Exercises

1. Implement a Symbol table class such that each symbol is associated with a numeric value. The two main methods are set() and get() as follows: the set() method associates the int value with the symbol, sym; while the get() method performs the complement of retrieving the int value previously associated with sym. Define appropriate exceptions so that clients of the Symbol table may respond to conditions appropriately. For example, when clients retrieve the value of a nonexistent symbol, they can either stop execution and display an error message or use a default value of 0. (Hint: You can use HashMap and Vector to store symbol-value pairs.)

   void set(String symbol, int value);
   int get(String symbol);

2. Write a program to read the file names specified in the command-line and copy their contents to the standard output. Implement a method to read the contents of the file, and write it out to the standard output stream with all lowercase characters converted to uppercase.