| Modifier and Type | Field and Description |
|---|---|
| protected int | charPositionInLine
The index of the character relative to the beginning of the line 0..n-1 |
| protected char[] | data
The data being scanned |
| protected int | lastMarker
Track the last mark() call result value for use in rewind(). |
| protected int | line
line number 1..n within the input |
| protected int | markDepth
tracks how deep mark() calls are nested |
| protected List | markers
A list of CharStreamState objects that tracks the stream state values line, charPositionInLine, and p that can change as you move through the input stream. |
| protected int | n
How many characters are actually in the buffer |
| public String | name
What is name or source of this char stream? |
| protected int | p
0..n-1 index into string of next char |
| Access | Constructor and Description |
|---|---|
| public | |
| public | |
| public | ANTLRStringStream(char[] data, int numberOfActualCharsInArray)
This is the preferred constructor as no data is copied |
| Modifier and Type | Method and Description |
|---|---|
| public void | |
| public int | getCharPositionInLine()
Implements org. |
| public int | getLine()
Implements org. |
| public String | getSourceName()
Implements org. |
| public int | index()
Implements org. |
| public int | LA(int i)
Implements org. |
| public int | |
| public int | mark()
Implements org. |
| public void | release(int marker)
Implements org. |
| public void | reset()
Reset the stream so that it's in the same state it was when the object was created *except* the data array is not touched. |
| public void | rewind(int m)
Implements org. |
| public void | rewind()
Implements org. |
| public void | seek(int index)
Implements org. |
| public void | |
| public void | setLine(int line)
Implements org. |
| public int | size()
Implements org. |
| public String | substring(int start, int stop)
Implements org. |
| public String |
| charPositionInLine | back to summary |
|---|---|
| protected int charPositionInLine The index of the character relative to the beginning of the line 0..n-1 | |
| data | back to summary |
|---|---|
| protected char[] data The data being scanned | |
| lastMarker | back to summary |
|---|---|
| protected int lastMarker Track the last mark() call result value for use in rewind(). | |
| line | back to summary |
|---|---|
| protected int line line number 1..n within the input | |
| markDepth | back to summary |
|---|---|
| protected int markDepth tracks how deep mark() calls are nested | |
| markers | back to summary |
|---|---|
| protected List<CharStreamState> markers A list of CharStreamState objects that tracks the stream state values line, charPositionInLine, and p that can change as you move through the input stream. Indexed from 1..markDepth. A null is kept @ index 0. Create upon first call to mark(). | |
| n | back to summary |
|---|---|
| protected int n How many characters are actually in the buffer | |
| name | back to summary |
|---|---|
| public String name What is name or source of this char stream? | |
| p | back to summary |
|---|---|
| protected int p 0..n-1 index into string of next char | |
| ANTLRStringStream | back to summary |
|---|---|
| public ANTLRStringStream() | |
| ANTLRStringStream | back to summary |
|---|---|
| public ANTLRStringStream(String input) Copy data in string to a local char array | |
| ANTLRStringStream | back to summary |
|---|---|
| public ANTLRStringStream(char[] data, int numberOfActualCharsInArray) This is the preferred constructor as no data is copied | |
| consume | back to summary |
|---|---|
| public void consume() Implements org.
| |
| getCharPositionInLine | back to summary |
|---|---|
| public int getCharPositionInLine() Implements org. Doc from org. The index of the character relative to the beginning of the line 0..n-1
| |
| getLine | back to summary |
|---|---|
| public int getLine() Implements org. Doc from org. ANTLR tracks the line information automatically
| |
| 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.
| |
| index | back to summary |
|---|---|
| public int index() Implements org. Return the current input symbol index 0..n where n indicates the last symbol has been read. The index is the index of char to be returned from LA(1).
| |
| 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 int LT(int i) Implements org. Doc from org. Get the ith character of lookahead. This is the same usually as LA(i). This will be used for labels in the generated lexer code. I'd prefer to return a char here type-wise, but it's probably better to be 32-bit clean and be consistent with LA.
| |
| 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.
| |
| 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.
| |
| reset | back to summary |
|---|---|
| public void reset() Reset the stream so that it's in the same state it was when the object was created *except* the data array is not touched. | |
| rewind | back to summary |
|---|---|
| public void rewind(int m) 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. consume() ahead until p==index; can't just set p=index as we must update line and charPositionInLine.
| |
| setCharPositionInLine | back to summary |
|---|---|
| public void setCharPositionInLine(int pos) Implements org.
| |
| setLine | back to summary |
|---|---|
| public void setLine(int line) Implements org. Doc from org. Because this stream can rewind, we need to be able to reset the line
| |
| 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.
| |
| substring | back to summary |
|---|---|
| public String substring(int start, int stop) Implements org. Doc from org. For infinite streams, you don't need this; primarily I'm providing a useful interface for action code. Just make sure actions don't use this on streams that don't support it.
| |
| toString | back to summary |
|---|---|
| public String toString() Overrides java. Doc from java. Returns a string representation of the object. | |