InputCharStream (Castor JavaDoc)

java.lang.Object
- org.exolab.castor.xml.dtd.parser.InputCharStream

All Implemented Interfaces:

CharStream
```
public final class InputCharStream
extends java.lang.Object
implements CharStream
```
An implementation of interface CharStream. Implements input character stream that maintains line and column number positions of the characters. It also has the capability to backup the stream to some extent.
The object of this class is constructed using java.io.Reader reader and it is left to constructor of the reader to set up character encoding correctly. This means that method read of the reader is used to get next characters, assuming it returns appropriate values. It is recommended to use class java.io.InputStreamReader as a reader, which allows to set desired character encoding. This class is an intermediate component between input character reader and the parser.
The code of this class is based on the class ASCII_CharStream - implementation of interface CharStream, that JavaCC would have generated with the following options set in a JavaCC grammar file:
```
    JAVA_UNICODE_ESCAPE = false;
    UNICODE_INPUT = false;
    USER_CHAR_STREAM = false; 
```
Note that this class is not fully JavaCC generated.
Version:

$Revision: 5962 $ $Date: 2003-03-03 00:05:44 -0700 (Mon, 03 Mar 2003) $

Author:

JavaCC, Alexander Totok

Field Summary

Fields
Modifier and Type	Field	Description
`(package private) int`	`available`
`int`	`bufpos`
`(package private) int`	`bufsize`
`static boolean`	`staticFlag`
`(package private) int`	`tokenBegin`

Constructor Summary

Constructors
Constructor	Description
`InputCharStream(java.io.Reader dstream)`	Constructor, instantiating the char stream to begin at 1-st line and 1-st column of `dstream`.
`InputCharStream(java.io.Reader dstream, int startline, int startcolumn)`	Constructor, allowing to specify start line and start column of the char stream.
`InputCharStream(java.io.Reader dstream, int startline, int startcolumn, int buffersize)`	Constructor, allowing to specify start line and start column of the char stream, and buffer size as well.

Method Summary

All Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method	Description
`void`	`adjustBeginLineColumn(int newLine, int newCol)`	Method to adjust line and column numbers for the start of a token.
`void`	`backup(int amount)`	Backs up the input stream by amount steps.
`char`	`BeginToken()`	Returns the next character that marks the beginning of the next token.
`void`	`Done()`	The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class.
`int`	`getBeginColumn()`	Returns the column number of the first character for current token (being matched after the last call to BeginTOken).
`int`	`getBeginLine()`	Returns the line number of the first character for current token (being matched after the last call to BeginTOken).
`int`	`getColumn()`	Deprecated.
`int`	`getEndColumn()`	Returns the column number of the last character for current token (being matched after the last call to BeginTOken).
`int`	`getEndLine()`	Returns the line number of the last character for current token (being matched after the last call to BeginTOken).
`java.lang.String`	`GetImage()`	Returns a string made up of characters from the marked token beginning to the current buffer position.
`int`	`getLine()`	Deprecated.
`char[]`	`GetSuffix(int len)`	Returns an array of characters that make up the suffix of length 'len' for the currently matched token.
`char`	`readChar()`	Returns the next character from the input stream.
`void`	`ReInit(java.io.Reader dstream)`	Reinitialization of the char stream, instantiating the char stream to begin at 1-st line and 1-st column of `dstream`.
`void`	`ReInit(java.io.Reader dstream, int startline, int startcolumn)`	Reinitialization of the char stream, allowing to specify start line and start column of the char stream.
`void`	`ReInit(java.io.Reader dstream, int startline, int startcolumn, int buffersize)`	Reinitialization of the char stream, allowing to specify start line and start column of the char stream, and buffer size as well.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Field Detail
  - staticFlag
```
public static final boolean staticFlag
```
    See Also:
    
    Constant Field Values
  - bufsize
```
int bufsize
```
  - available
```
int available
```
  - tokenBegin
```
int tokenBegin
```
  - bufpos
```
public int bufpos
```
- Constructor Detail
  - InputCharStream
```
public InputCharStream(java.io.Reader dstream,
                       int startline,
                       int startcolumn,
                       int buffersize)
```
    Constructor, allowing to specify start line and start column of the char stream, and buffer size as well.
  - InputCharStream
```
public InputCharStream(java.io.Reader dstream,
                       int startline,
                       int startcolumn)
```
    Constructor, allowing to specify start line and start column of the char stream.
  - InputCharStream
```
public InputCharStream(java.io.Reader dstream)
```
    Constructor, instantiating the char stream to begin at 1-st line and 1-st column of dstream.
- Method Detail
  - BeginToken
```
public final char BeginToken()
                      throws java.io.IOException
```
    Description copied from interface: CharStream
    
    Returns the next character that marks the beginning of the next token. All characters must remain in the buffer between two successive calls to this method to implement backup correctly.
    
    Specified by:
    
    BeginToken in interface CharStream
    
    Throws:
    
    java.io.IOException
  - readChar
```
public final char readChar()
                    throws java.io.IOException
```
    Returns the next character from the input stream. The only method whose implementation is different from its original in the ASCII_CharStream class.
    
    Specified by:
    
    readChar in interface CharStream
    
    Throws:
    
    java.io.IOException
  - getColumn
```
public final int getColumn()
```
    Deprecated.
    
    Description copied from interface: CharStream
    
    Returns the column position of the character last read.
    
    Specified by:
    
    getColumn in interface CharStream
    
    See Also:
    
    getEndColumn()
  - getLine
```
public final int getLine()
```
    Deprecated.
    
    Description copied from interface: CharStream
    
    Returns the line number of the character last read.
    
    Specified by:
    
    getLine in interface CharStream
    
    See Also:
    
    getEndLine()
  - getEndColumn
```
public final int getEndColumn()
```
    Description copied from interface: CharStream
    
    Returns the column number of the last character for current token (being matched after the last call to BeginTOken).
    
    Specified by:
    
    getEndColumn in interface CharStream
  - getEndLine
```
public final int getEndLine()
```
    Description copied from interface: CharStream
    
    Returns the line number of the last character for current token (being matched after the last call to BeginTOken).
    
    Specified by:
    
    getEndLine in interface CharStream
  - getBeginColumn
```
public final int getBeginColumn()
```
    Description copied from interface: CharStream
    
    Returns the column number of the first character for current token (being matched after the last call to BeginTOken).
    
    Specified by:
    
    getBeginColumn in interface CharStream
  - getBeginLine
```
public final int getBeginLine()
```
    Description copied from interface: CharStream
    
    Returns the line number of the first character for current token (being matched after the last call to BeginTOken).
    
    Specified by:
    
    getBeginLine in interface CharStream
  - backup
```
public final void backup(int amount)
```
    Description copied from interface: CharStream
    
    Backs up the input stream by amount steps. Lexer calls this method if it had already read some characters, but could not use them to match a (longer) token. So, they will be used again as the prefix of the next token and it is the implemetation's responsibility to do this right.
    
    Specified by:
    
    backup in interface CharStream
  - ReInit
```
public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn,
                   int buffersize)
```
    Reinitialization of the char stream, allowing to specify start line and start column of the char stream, and buffer size as well.
  - ReInit
```
public void ReInit(java.io.Reader dstream,
                   int startline,
                   int startcolumn)
```
    Reinitialization of the char stream, allowing to specify start line and start column of the char stream.
  - ReInit
```
public void ReInit(java.io.Reader dstream)
```
    Reinitialization of the char stream, instantiating the char stream to begin at 1-st line and 1-st column of dstream.
  - GetImage
```
public final java.lang.String GetImage()
```
    Description copied from interface: CharStream
    
    Returns a string made up of characters from the marked token beginning to the current buffer position. Implementations have the choice of returning anything that they want to. For example, for efficiency, one might decide to just return null, which is a valid implementation.
    
    Specified by:
    
    GetImage in interface CharStream
  - GetSuffix
```
public final char[] GetSuffix(int len)
```
    Description copied from interface: CharStream
    Returns an array of characters that make up the suffix of length 'len' for the currently matched token. This is used to build up the matched string for use in actions in the case of MORE. A simple and inefficient implementation of this is as follows :
```
   {
      String t = GetImage();
      return t.substring(t.length() - len, t.length()).toCharArray();
   }
 
```
    Specified by:
    
    GetSuffix in interface CharStream
  - Done
```
public void Done()
```
    Description copied from interface: CharStream
    
    The lexer calls this function to indicate that it is done with the stream and hence implementations can free any resources held by this class. Again, the body of this function can be just empty and it will not affect the lexer's operation.
    
    Specified by:
    
    Done in interface CharStream
  - adjustBeginLineColumn
```
public void adjustBeginLineColumn(int newLine,
                                  int newCol)
```
    Method to adjust line and column numbers for the start of a token.

Class InputCharStream

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

staticFlag

bufsize

available

tokenBegin

bufpos

Constructor Detail

InputCharStream

InputCharStream

InputCharStream

Method Detail

BeginToken

readChar

getColumn

getLine

getEndColumn

getEndLine

getBeginColumn

getBeginLine

backup

ReInit

ReInit

ReInit

GetImage

GetSuffix

Done

adjustBeginLineColumn