public final class InputCharStream extends Object implements CharStream
CharStream.
Implements input character stream that maintains line and column number positions of the
characters. It also has the capability to backup the stream to some extent.java.io.Reader
reader and it is left to constructor of the reader to set up character encoding
correctly. This means that method read of the reader is
used to get next characters, assuming it returns appropriate values. It is recommended to use
class java.io.InputStreamReader as a reader, which
allows to set desired character encoding. This class is an intermediate component between input
character reader and the parser.CharStream, that JavaCC would have
generated with the following options set in a JavaCC grammar file:
JAVA_UNICODE_ESCAPE = false; UNICODE_INPUT = false; USER_CHAR_STREAM = false;Note that this class is not fully JavaCC generated.
| Modifier and Type | Field and Description |
|---|---|
int |
bufpos |
static boolean |
staticFlag |
| Constructor and Description |
|---|
InputCharStream(Reader dstream)
Constructor, instantiating the char stream to begin at 1-st line and 1-st column of
dstream.
|
InputCharStream(Reader dstream,
int startline,
int startcolumn)
Constructor, allowing to specify start line and start column of the char stream.
|
InputCharStream(Reader dstream,
int startline,
int startcolumn,
int buffersize)
Constructor, allowing to specify start line and start column of the char stream, and buffer
size as well.
|
| Modifier and Type | Method and Description |
|---|---|
void |
adjustBeginLineColumn(int newLine,
int newCol)
Method to adjust line and column numbers for the start of a token.
|
void |
backup(int amount)
Backs up the input stream by amount steps.
|
char |
BeginToken()
Returns the next character that marks the beginning of the next token.
|
void |
Done()
The lexer calls this function to indicate that it is done with the stream and hence
implementations can free any resources held by this class.
|
int |
getBeginColumn()
Returns the column number of the first character for current token (being matched after the
last call to BeginTOken).
|
int |
getBeginLine()
Returns the line number of the first character for current token (being matched after the last
call to BeginTOken).
|
int |
getColumn()
Deprecated.
|
int |
getEndColumn()
Returns the column number of the last character for current token (being matched after the last
call to BeginTOken).
|
int |
getEndLine()
Returns the line number of the last character for current token (being matched after the last
call to BeginTOken).
|
String |
GetImage()
Returns a string made up of characters from the marked token beginning to the current buffer
position.
|
int |
getLine()
Deprecated.
|
char[] |
GetSuffix(int len)
Returns an array of characters that make up the suffix of length 'len' for the currently
matched token.
|
char |
readChar()
Returns the next character from the input stream.
|
void |
ReInit(Reader dstream)
Reinitialization of the char stream, instantiating the char stream to begin at 1-st line and
1-st column of dstream.
|
void |
ReInit(Reader dstream,
int startline,
int startcolumn)
Reinitialization of the char stream, allowing to specify start line and start column of the
char stream.
|
void |
ReInit(Reader dstream,
int startline,
int startcolumn,
int buffersize)
Reinitialization of the char stream, allowing to specify start line and start column of the
char stream, and buffer size as well.
|
public static final boolean staticFlag
public int bufpos
public InputCharStream(Reader dstream, int startline, int startcolumn, int buffersize)
public InputCharStream(Reader dstream, int startline, int startcolumn)
public InputCharStream(Reader dstream)
public final char BeginToken()
throws IOException
CharStreamBeginToken in interface CharStreamIOExceptionpublic final char readChar()
throws IOException
readChar in interface CharStreamIOExceptionpublic final int getColumn()
CharStreamgetColumn in interface CharStreamgetEndColumn()public final int getLine()
CharStreamgetLine in interface CharStreamgetEndLine()public final int getEndColumn()
CharStreamgetEndColumn in interface CharStreampublic final int getEndLine()
CharStreamgetEndLine in interface CharStreampublic final int getBeginColumn()
CharStreamgetBeginColumn in interface CharStreampublic final int getBeginLine()
CharStreamgetBeginLine in interface CharStreampublic final void backup(int amount)
CharStreambackup in interface CharStreampublic void ReInit(Reader dstream, int startline, int startcolumn, int buffersize)
public void ReInit(Reader dstream, int startline, int startcolumn)
public void ReInit(Reader dstream)
public final String GetImage()
CharStreamGetImage in interface CharStreampublic final char[] GetSuffix(int len)
CharStream
{
String t = GetImage();
return t.substring(t.length() - len, t.length()).toCharArray();
}
GetSuffix in interface CharStreampublic void Done()
CharStreamDone in interface CharStreampublic void adjustBeginLineColumn(int newLine,
int newCol)
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