Class Scanner
java.lang.Object
|
+--Scanner
- public class Scanner
- extends Object
Scan an input stream looking for tokens defined for a simple language.
Constructor Summary |
Scanner(CompilerIO io)
Construct a new Scanner object. |
Method Summary |
Token |
nextToken()
Starting with the current character, identify the next Token and
return the appropriate Token object to the caller. |
Methods inherited from class java.lang.Object |
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait |
Scanner
public Scanner(CompilerIO io)
- Construct a new Scanner object. The first line of the source
file is read in here but no processing is actually done until
the first call to nextToken. The keywords HashMap is initialized
here.
- Parameters:
io
- the CompilerIO object to use in reading and writing files.
nextToken
public Token nextToken()
- Starting with the current character, identify the next Token and
return the appropriate Token object to the caller. This method
calls the private helper methods getCurrentCharacter and
acceptCurrentCharacter repeatedly to inspect and advance past
characters until it decides that it has found something
worthy of being reported as a Token.
- Returns:
- the appropriate Token object