 | Report generated by Clover Code Coverage v2.3.0 Fri May 9 2008 10:54:33 EST. |
Site License registered to Cenqua |
|
|||||||||||||||||||||||||||||||||||||||||||||||||||||||||
| CharStream | Line # 19 | 0 | 0 | - |
-1.0
|
||||||||||||||||||||||||||||||||||||||||||||||||||||
| No Tests | |||
| 1 | /* Generated By:JavaCC: Do not edit this line. CharStream.java Version 3.0 */ | |
| 2 | package org.apache.lucene.analysis.standard; | |
| 3 | ||
| 4 | /** | |
| 5 | * This interface describes a character stream that maintains line and | |
| 6 | * column number positions of the characters. It also has the capability | |
| 7 | * to backup the stream to some extent. An implementation of this | |
| 8 | * interface is used in the TokenManager implementation generated by | |
| 9 | * JavaCCParser. | |
| 10 | * | |
| 11 | * All the methods except backup can be implemented in any fashion. backup | |
| 12 | * needs to be implemented correctly for the correct operation of the lexer. | |
| 13 | * Rest of the methods are all used to get information like line number, | |
| 14 | * column number and the String that constitutes a token and are not used | |
| 15 | * by the lexer. Hence their implementation won't affect the generated lexer's | |
| 16 | * operation. | |
| 17 | */ | |
| 18 | ||
| 19 | public interface CharStream { | |
| 20 | ||
| 21 | /** | |
| 22 | * Returns the next character from the selected input. The method | |
| 23 | * of selecting the input is the responsibility of the class | |
| 24 | * implementing this interface. Can throw any java.io.IOException. | |
| 25 | */ | |
| 26 | char readChar() throws java.io.IOException; | |
| 27 | ||
| 28 | /** | |
| 29 | * Returns the column position of the character last read. | |
| 30 | * @deprecated | |
| 31 | * @see #getEndColumn | |
| 32 | */ | |
| 33 | int getColumn(); | |
| 34 | ||
| 35 | /** | |
| 36 | * Returns the line number of the character last read. | |
| 37 | * @deprecated | |
| 38 | * @see #getEndLine | |
| 39 | */ | |
| 40 | int getLine(); | |
| 41 | ||
| 42 | /** | |
| 43 | * Returns the column number of the last character for current token (being | |
| 44 | * matched after the last call to BeginTOken). | |
| 45 | */ | |
| 46 | int getEndColumn(); | |
| 47 | ||
| 48 | /** | |
| 49 | * Returns the line number of the last character for current token (being | |
| 50 | * matched after the last call to BeginTOken). | |
| 51 | */ | |
| 52 | int getEndLine(); | |
| 53 | ||
| 54 | /** | |
| 55 | * Returns the column number of the first character for current token (being | |
| 56 | * matched after the last call to BeginTOken). | |
| 57 | */ | |
| 58 | int getBeginColumn(); | |
| 59 | ||
| 60 | /** | |
| 61 | * Returns the line number of the first character for current token (being | |
| 62 | * matched after the last call to BeginTOken). | |
| 63 | */ | |
| 64 | int getBeginLine(); | |
| 65 | ||
| 66 | /** | |
| 67 | * Backs up the input stream by amount steps. Lexer calls this method if it | |
| 68 | * had already read some characters, but could not use them to match a | |
| 69 | * (longer) token. So, they will be used again as the prefix of the next | |
| 70 | * token and it is the implemetation's responsibility to do this right. | |
| 71 | */ | |
| 72 | void backup(int amount); | |
| 73 | ||
| 74 | /** | |
| 75 | * Returns the next character that marks the beginning of the next token. | |
| 76 | * All characters must remain in the buffer between two successive calls | |
| 77 | * to this method to implement backup correctly. | |
| 78 | */ | |
| 79 | char BeginToken() throws java.io.IOException; | |
| 80 | ||
| 81 | /** | |
| 82 | * Returns a string made up of characters from the marked token beginning | |
| 83 | * to the current buffer position. Implementations have the choice of returning | |
| 84 | * anything that they want to. For example, for efficiency, one might decide | |
| 85 | * to just return null, which is a valid implementation. | |
| 86 | */ | |
| 87 | String GetImage(); | |
| 88 | ||
| 89 | /** | |
| 90 | * Returns an array of characters that make up the suffix of length 'len' for | |
| 91 | * the currently matched token. This is used to build up the matched string | |
| 92 | * for use in actions in the case of MORE. A simple and inefficient | |
| 93 | * implementation of this is as follows : | |
| 94 | * | |
| 95 | * { | |
| 96 | * String t = GetImage(); | |
| 97 | * return t.substring(t.length() - len, t.length()).toCharArray(); | |
| 98 | * } | |
| 99 | */ | |
| 100 | char[] GetSuffix(int len); | |
| 101 | ||
| 102 | /** | |
| 103 | * The lexer calls this function to indicate that it is done with the stream | |
| 104 | * and hence implementations can free any resources held by this class. | |
| 105 | * Again, the body of this function can be just empty and it will not | |
| 106 | * affect the lexer's operation. | |
| 107 | */ | |
| 108 | void Done(); | |
| 109 | ||
| 110 | } | |
|
||||||||||