| Modifier and Type | Field and Description |
|---|---|
| protected DebugEventListener | |
| protected boolean | |
| public TokenStream | |
| protected int | lastMarker
Track the last mark() call result value for use in rewind(). |
| Access | Constructor and Description |
|---|---|
| public |
| Modifier and Type | Method and Description |
|---|---|
| public void | |
| protected void | |
| public Token | |
| public String | getSourceName()
Implements org. |
| public TokenSource | getTokenSource()
Implements org. |
| public int | index()
Implements org. |
| public int | LA(int i)
Implements org. |
| public Token | LT(int i)
Implements org. |
| public int | mark()
Implements org. |
| public int | range()
Implements org. |
| public void | release(int marker)
Implements org. |
| public void | rewind(int marker)
Implements org. |
| public void | rewind()
Implements org. |
| public void | seek(int index)
Implements org. |
| public void | |
| public int | size()
Implements org. |
| public String | |
| public String | toString(int start, int stop)
Implements org. |
| public String | toString(Token start, Token stop)
Implements org. |
| dbg | back to summary |
|---|---|
| protected DebugEventListener dbg | |
| initialStreamState | back to summary |
|---|---|
| protected boolean initialStreamState | |
| input | back to summary |
|---|---|
| public TokenStream input | |
| lastMarker | back to summary |
|---|---|
| protected int lastMarker Track the last mark() call result value for use in rewind(). | |
| DebugTokenStream | back to summary |
|---|---|
| public DebugTokenStream(TokenStream input, DebugEventListener dbg) | |
| consume | back to summary |
|---|---|
| public void consume() Implements org.
| |
| consumeInitialHiddenTokens | back to summary |
|---|---|
| protected void consumeInitialHiddenTokens() | |
| get | back to summary |
|---|---|
| public Token get(int i) Implements org. Doc from org. Get a token at an absolute index i; 0..n-1. This is really only needed for profiling and debugging and token stream rewriting. If you don't want to buffer up tokens, then this method makes no sense for you. Naturally you can't use the rewrite stream feature. I believe DebugTokenStream can easily be altered to not use this method, removing the dependency.
| |
| getSourceName | back to summary |
|---|---|
| public String getSourceName() Implements org. Doc from org. Where are you getting symbols from? Normally, implementations will pass the buck all the way to the lexer who can ask its input stream for the file name or whatever.
| |
| getTokenSource | back to summary |
|---|---|
| public TokenSource getTokenSource() Implements org. Doc from org. Where is this stream pulling tokens from? This is not the name, but the object that provides Token objects.
| |
| index | back to summary |
|---|---|
| public int index() Implements org. Doc from org. Return the current input symbol index 0..n where n indicates the last symbol has been read. The index is the symbol about to be read not the most recently read symbol.
| |
| LA | back to summary |
|---|---|
| public int LA(int i) Implements org. Doc from org. Get int at current input pointer + i ahead where i=1 is next int. Negative indexes are allowed. LA(-1) is previous token (token just matched). LA(-i) where i is before first token should yield -1, invalid char / EOF.
| |
| LT | back to summary |
|---|---|
| public Token LT(int i) Implements org. Doc from org. Get Token at current input pointer + i ahead where i=1 is next Token. i<0 indicates tokens in the past. So -1 is previous token and -2 is two tokens ago. LT(0) is undefined. For i>=n, return Token.EOFToken. Return null for LT(0) and any index that results in an absolute address that is negative.
| |
| mark | back to summary |
|---|---|
| public int mark() Implements org. Doc from org. Tell the stream to start buffering if it hasn't already. Return current input position, index(), or some other marker so that when passed to rewind() you get back to the same spot. rewind(mark()) should not affect the input cursor. The Lexer track line/col info as well as input index so its markers are not pure input indexes. Same for tree node streams.
| |
| range | back to summary |
|---|---|
| public int range() Implements org. Doc from org. How far ahead has the stream been asked to look? The return value is a valid index from 0..n-1.
| |
| release | back to summary |
|---|---|
| public void release(int marker) Implements org. Doc from org. You may want to commit to a backtrack but don't want to force the stream to keep bookkeeping objects around for a marker that is no longer necessary. This will have the same behavior as rewind() except it releases resources without the backward seek. This must throw away resources for all markers back to the marker argument. So if you're nested 5 levels of mark(), and then release(2) you have to release resources for depths 2..5.
| |
| rewind | back to summary |
|---|---|
| public void rewind(int marker) Implements org. Doc from org. Reset the stream so that next call to index would return marker. The marker will usually be index() but it doesn't have to be. It's just a marker to indicate what state the stream was in. This is essentially calling release() and seek(). If there are markers created after this marker argument, this routine must unroll them like a stack. Assume the state the stream was in when this marker was created.
| |
| rewind | back to summary |
|---|---|
| public void rewind() Implements org. Doc from org. Rewind to the input position of the last marker. Used currently only after a cyclic DFA and just before starting a sem/syn predicate to get the input position back to the start of the decision. Do not "pop" the marker off the state. mark(i) and rewind(i) should balance still. It is like invoking rewind(last marker) but it should not "pop" the marker off. It's like seek(last marker's input position).
| |
| seek | back to summary |
|---|---|
| public void seek(int index) Implements org. Doc from org. Set the input cursor to the position indicated by index. This is normally used to seek ahead in the input stream. No buffering is required to do this unless you know your stream will use seek to move backwards such as when backtracking. This is different from rewind in its multi-directional requirement and in that its argument is strictly an input cursor (index). For char streams, seeking forward must update the stream state such as line number. For seeking backwards, you will be presumably backtracking using the mark/rewind mechanism that restores state and so this method does not need to update state when seeking backwards. Currently, this method is only used for efficient backtracking using memoization, but in the future it may be used for incremental parsing. The index is 0..n-1. A seek to position i means that LA(1) will return the ith symbol. So, seeking to 0 means LA(1) will return the first element in the stream.
| |
| setDebugListener | back to summary |
|---|---|
| public void setDebugListener(DebugEventListener dbg) | |
| size | back to summary |
|---|---|
| public int size() Implements org. Doc from org. Only makes sense for streams that buffer everything up probably, but might be useful to display the entire stream or for testing. This value includes a single EOF.
| |
| toString | back to summary |
|---|---|
| public String toString() Overrides java. Doc from java. Returns a string representation of the object. | |
| toString | back to summary |
|---|---|
| public String toString(int start, int stop) Implements org. Doc from org. Return the text of all tokens from start to stop, inclusive. If the stream does not buffer all the tokens then it can just return "" or null; Users should not access $ruleLabel.text in an action of course in that case.
| |
| toString | back to summary |
|---|---|
| public String toString(Token start, Token stop) Implements org. Doc from org. Because the user is not required to use a token with an index stored in it, we must provide a means for two token objects themselves to indicate the start/end location. Most often this will just delegate to the other toString(int,int). This is also parallel with the TreeNodeStream.toString(Object,Object).
| |