org.antlr.runtime.debug.ParseTreeBuilder Class Reference
Public Member Functions | |
| ParseTreeBuilder (String grammarName) | |
| ParseTree | getTree () |
| ParseTree | create (Object payload) |
| ParseTree | epsilonNode () |
| void | enterDecision (int d) |
| void | exitDecision (int i) |
| void | enterRule (String filename, String ruleName) |
| void | exitRule (String filename, String ruleName) |
| void | consumeToken (Token token) |
| void | consumeHiddenToken (Token token) |
| void | recognitionException (RecognitionException e) |
Static Public Attributes | |
| static final String | EPSILON_PAYLOAD = "<epsilon>" |
Package Attributes | |
| Stack | callStack = new Stack() |
| List | hiddenTokens = new ArrayList() |
| int | backtracking = 0 |
Detailed Description
This parser listener tracks rule entry/exit and token matches to build a simple parse tree using ParseTree nodes.Definition at line 41 of file ParseTreeBuilder.java.
Constructor & Destructor Documentation
| org.antlr.runtime.debug.ParseTreeBuilder.ParseTreeBuilder | ( | String | grammarName | ) |
Definition at line 48 of file ParseTreeBuilder.java.
Member Function Documentation
| ParseTree org.antlr.runtime.debug.ParseTreeBuilder.getTree | ( | ) |
Definition at line 53 of file ParseTreeBuilder.java.
| ParseTree org.antlr.runtime.debug.ParseTreeBuilder.create | ( | Object | payload | ) |
What kind of node to create. You might want to override so I factored out creation here.
Definition at line 60 of file ParseTreeBuilder.java.
| ParseTree org.antlr.runtime.debug.ParseTreeBuilder.epsilonNode | ( | ) |
Definition at line 64 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.enterDecision | ( | int | d | ) |
Backtracking or cyclic DFA, don't want to add nodes to tree
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 69 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.exitDecision | ( | int | i | ) |
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 70 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.enterRule | ( | String | grammarFileName, | |
| String | ruleName | |||
| ) |
The parser has just entered a rule. No decision has been made about which alt is predicted. This is fired AFTER init actions have been executed. Attributes are defined and available etc... The grammarFileName allows composite grammars to jump around among multiple grammar files.
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 72 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.exitRule | ( | String | grammarFileName, | |
| String | ruleName | |||
| ) |
This is the last thing executed before leaving a rule. It is executed even if an exception is thrown. This is triggered after error reporting and recovery have occurred (unless the exception is not caught in this rule). This implies an "exitAlt" event. The grammarFileName allows composite grammars to jump around among multiple grammar files.
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 80 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.consumeToken | ( | Token | t | ) |
An input token was consumed; matched by any kind of element. Trigger after the token was matched by things like match(), matchAny().
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 89 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.consumeHiddenToken | ( | Token | t | ) |
An off-channel input token was consumed. Trigger after the token was matched by things like match(), matchAny(). (unless of course the hidden token is first stuff in the input stream).
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 98 of file ParseTreeBuilder.java.
| void org.antlr.runtime.debug.ParseTreeBuilder.recognitionException | ( | RecognitionException | e | ) |
A recognition exception occurred such as NoViableAltException. I made this a generic event so that I can alter the exception hierachy later without having to alter all the debug objects.
Upon error, the stack of enter rule/subrule must be properly unwound. If no viable alt occurs it is within an enter/exit decision, which also must be rewound. Even the rewind for each mark must be unwount. In the Java target this is pretty easy using try/finally, if a bit ugly in the generated code. The rewind is generated in DFA.predict() actually so no code needs to be generated for that. For languages w/o this "finally" feature (C++?), the target implementor will have to build an event stack or something.
Across a socket for remote debugging, only the RecognitionException data fields are transmitted. The token object or whatever that caused the problem was the last object referenced by LT. The immediately preceding LT event should hold the unexpected Token or char.
Here is a sample event trace for grammar:
b : C ({;}A|B) // {;} is there to prevent A|B becoming a set | D ;
The sequence for this rule (with no viable alt in the subrule) for input 'c c' (there are 3 tokens) is:
commence LT(1) enterRule b location 7 1 enter decision 3 LT(1) exit decision 3 enterAlt1 location 7 5 LT(1) consumeToken [c/<4>,1:0] location 7 7 enterSubRule 2 enter decision 2 LT(1) LT(1) recognitionException NoViableAltException 2 1 2 exit decision 2 exitSubRule 2 beginResync LT(1) consumeToken [c/<4>,1:1] LT(1) endResync LT(-1) exitRule b terminate
Reimplemented from org.antlr.runtime.debug.BlankDebugEventListener.
Definition at line 103 of file ParseTreeBuilder.java.
Member Data Documentation
final String org.antlr.runtime.debug.ParseTreeBuilder.EPSILON_PAYLOAD = "<epsilon>" [static] |
Definition at line 42 of file ParseTreeBuilder.java.
Stack org.antlr.runtime.debug.ParseTreeBuilder.callStack = new Stack() [package] |
Definition at line 44 of file ParseTreeBuilder.java.
List org.antlr.runtime.debug.ParseTreeBuilder.hiddenTokens = new ArrayList() [package] |
Definition at line 45 of file ParseTreeBuilder.java.
int org.antlr.runtime.debug.ParseTreeBuilder.backtracking = 0 [package] |
Definition at line 46 of file ParseTreeBuilder.java.
The documentation for this class was generated from the following file:
- /Users/parrt/antlr/code/antlr/main/runtime/Java/src/org/antlr/runtime/debug/ParseTreeBuilder.java
