/* Generated By:JavaCC: Do not edit this line. CharStream.java Version 5.0 */
/* JavaCCOptions:STATIC=false,SUPPORT_CLASS_VISIBILITY_PUBLIC=true */
package org.apache.lucene.queryparser.surround.parser;
/**
* This interface describes a character stream that maintains line and
* column number positions of the characters. It also has the capability
* to backup the stream to some extent. An implementation of this
* interface is used in the TokenManager implementation generated by
* JavaCCParser.
*
* All the methods except backup can be implemented in any fashion. backup
* needs to be implemented correctly for the correct operation of the lexer.
* Rest of the methods are all used to get information like line number,
* column number and the String that constitutes a token and are not used
* by the lexer. Hence their implementation won't affect the generated lexer's
* operation.
*/
public
interface CharStream {
/**
* Returns the next character from the selected input. The method
* of selecting the input is the responsibility of the class
* implementing this interface. Can throw any java.io.IOException.
*/
char readChar() throws java.io.IOException;
@Deprecated
/**
* Returns the column position of the character last read.
* @deprecated
* @see #getEndColumn
*/
int getColumn();
@Deprecated
/**
* Returns the line number of the character last read.
* @deprecated
* @see #getEndLine
*/
int getLine();
/**
* Returns the column number of the last character for current token (being
* matched after the last call to BeginTOken).
*/
int getEndColumn();
/**
* Returns the line number of the last character for current token (being
* matched after the last call to BeginTOken).
*/
int getEndLine();
/**
* Returns the column number of the first character for current token (being
* matched after the last call to BeginTOken).
*/
int getBeginColumn();
/**
* Returns the line number of the first character for current token (being
* matched after the last call to BeginTOken).
*/
int getBeginLine();
/**
* 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.
*/
void backup(int amount);
/**
* 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.
*/
char BeginToken() throws java.io.IOException;
/**
* 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.
*/
String GetImage();
/**
* 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();
* }
*/
char[] GetSuffix(int len);
/**
* 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.
*/
void Done();
}
/* JavaCC - OriginalChecksum=5ca20c9145f29a0f8909470a7f949fe4 (do not edit this line) */