org.antlr.runtime.tree.RewriteRuleElementStream Class Reference
Public Member Functions | |
| RewriteRuleElementStream (TreeAdaptor adaptor, String elementDescription) | |
| RewriteRuleElementStream (TreeAdaptor adaptor, String elementDescription, Object oneElement) | |
| RewriteRuleElementStream (TreeAdaptor adaptor, String elementDescription, List elements) | |
| void | reset () |
| void | add (Object el) |
| Object | nextTree () |
| boolean | hasNext () |
| int | size () |
| String | getDescription () |
Protected Member Functions | |
| Object | _next () |
| abstract Object | dup (Object el) |
| Object | toTree (Object el) |
Protected Attributes | |
| int | cursor = 0 |
| Object | singleElement |
| List | elements |
| boolean | dirty = false |
| String | elementDescription |
| TreeAdaptor | adaptor |
Detailed Description
A generic list of elements tracked in an alternative to be used in a -> rewrite rule. We need to subclass to fill in the next() method, which returns either an AST node wrapped around a token payload or an existing subtree.Once you start next()ing, do not try to add more elements. It will break the cursor tracking I believe.
TODO: add mechanism to detect/puke on modification after reading from stream
Definition at line 49 of file RewriteRuleElementStream.java.
Constructor & Destructor Documentation
| org.antlr.runtime.tree.RewriteRuleElementStream.RewriteRuleElementStream | ( | TreeAdaptor | adaptor, | |
| String | elementDescription | |||
| ) |
Definition at line 78 of file RewriteRuleElementStream.java.
| org.antlr.runtime.tree.RewriteRuleElementStream.RewriteRuleElementStream | ( | TreeAdaptor | adaptor, | |
| String | elementDescription, | |||
| Object | oneElement | |||
| ) |
Create a stream with one element
Definition at line 84 of file RewriteRuleElementStream.java.
| org.antlr.runtime.tree.RewriteRuleElementStream.RewriteRuleElementStream | ( | TreeAdaptor | adaptor, | |
| String | elementDescription, | |||
| List | elements | |||
| ) |
Create a stream, but feed off an existing list
Definition at line 93 of file RewriteRuleElementStream.java.
Member Function Documentation
| void org.antlr.runtime.tree.RewriteRuleElementStream.reset | ( | ) |
Reset the condition of this stream so that it appears we have not consumed any of its elements. Elements themselves are untouched. Once we reset the stream, any future use will need duplicates. Set the dirty bit.
Definition at line 107 of file RewriteRuleElementStream.java.
| void org.antlr.runtime.tree.RewriteRuleElementStream.add | ( | Object | el | ) |
Definition at line 112 of file RewriteRuleElementStream.java.
| Object org.antlr.runtime.tree.RewriteRuleElementStream.nextTree | ( | ) |
Return the next element in the stream. If out of elements, throw an exception unless size()==1. If size is 1, then return elements[0]. Return a duplicate node/subtree if stream is out of elements and size==1. If we've already used the element, dup (dirty bit set).
Definition at line 137 of file RewriteRuleElementStream.java.
| Object org.antlr.runtime.tree.RewriteRuleElementStream._next | ( | ) | [protected] |
do the work of getting the next element, making sure that it's a tree node or subtree. Deal with the optimization of single- element list versus list of size > 1. Throw an exception if the stream is empty or we're out of elements and size>1. protected so you can override in a subclass if necessary.
Definition at line 155 of file RewriteRuleElementStream.java.
| abstract Object org.antlr.runtime.tree.RewriteRuleElementStream.dup | ( | Object | el | ) | [protected, pure virtual] |
When constructing trees, sometimes we need to dup a token or AST subtree. Dup'ing a token means just creating another AST node around it. For trees, you must call the adaptor.dupTree() unless the element is for a tree root; then it must be a node dup.
Implemented in org.antlr.runtime.tree.RewriteRuleNodeStream, org.antlr.runtime.tree.RewriteRuleSubtreeStream, and org.antlr.runtime.tree.RewriteRuleTokenStream.
| Object org.antlr.runtime.tree.RewriteRuleElementStream.toTree | ( | Object | el | ) | [protected] |
Ensure stream emits trees; tokens must be converted to AST nodes. AST nodes can be passed through unmolested.
Reimplemented in org.antlr.runtime.tree.RewriteRuleNodeStream, and org.antlr.runtime.tree.RewriteRuleTokenStream.
Definition at line 188 of file RewriteRuleElementStream.java.
| boolean org.antlr.runtime.tree.RewriteRuleElementStream.hasNext | ( | ) |
Definition at line 192 of file RewriteRuleElementStream.java.
| int org.antlr.runtime.tree.RewriteRuleElementStream.size | ( | ) |
Definition at line 197 of file RewriteRuleElementStream.java.
| String org.antlr.runtime.tree.RewriteRuleElementStream.getDescription | ( | ) |
Definition at line 208 of file RewriteRuleElementStream.java.
Member Data Documentation
int org.antlr.runtime.tree.RewriteRuleElementStream.cursor = 0 [protected] |
Cursor 0..n-1. If singleElement!=null, cursor is 0 until you next(), which bumps it to 1 meaning no more elements.
Definition at line 53 of file RewriteRuleElementStream.java.
Object org.antlr.runtime.tree.RewriteRuleElementStream.singleElement [protected] |
Track single elements w/o creating a list. Upon 2nd add, alloc list
Definition at line 56 of file RewriteRuleElementStream.java.
List org.antlr.runtime.tree.RewriteRuleElementStream.elements [protected] |
The list of tokens or subtrees we are tracking
Definition at line 59 of file RewriteRuleElementStream.java.
boolean org.antlr.runtime.tree.RewriteRuleElementStream.dirty = false [protected] |
Once a node / subtree has been used in a stream, it must be dup'd from then on. Streams are reset after subrules so that the streams can be reused in future subrules. So, reset must set a dirty bit. If dirty, then next() always returns a dup.
I wanted to use "naughty bit" here, but couldn't think of a way to use "naughty".
Definition at line 69 of file RewriteRuleElementStream.java.
String org.antlr.runtime.tree.RewriteRuleElementStream.elementDescription [protected] |
The element or stream description; usually has name of the token or rule reference that this list tracks. Can include rulename too, but the exception would track that info.
Definition at line 75 of file RewriteRuleElementStream.java.
Definition at line 76 of file RewriteRuleElementStream.java.
The documentation for this class was generated from the following file:
- /Users/parrt/antlr/code/antlr/main/runtime/Java/src/org/antlr/runtime/tree/RewriteRuleElementStream.java
