org.lsmp.djep.xjep

Class PrintVisitor

java.lang.Object

org.lsmp.djep.xjep.DoNothingVisitor

org.lsmp.djep.xjep.ErrorCatchingVisitor

org.lsmp.djep.xjep.PrintVisitor

All Implemented Interfaces:

ParserVisitor

Direct Known Subclasses:

DPrintVisitor

public class PrintVisitor
extends ErrorCatchingVisitor

Prints an expression. Prints the expression with lots of brackets. ((-1.0)/sqrt((1.0-(x^2.0)))). To use

 XJep j = ...; Node in = ...;
 j.print(in,"x");
 

Since:

Dec 04 and NumberFormat object can be supplied to modify printing of numbers., 21 Dec 04 PrintVisitor can now cope with 3 or more arguments to + and *.

See Also:

XJep.print(Node), XJep.print(Node, PrintStream), XJep.println(Node), XJep.println(Node, PrintStream), XJep.toString(Node)

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
static interface	PrintVisitor.PrintRulesI This interface specifies the method needed to implement a special print rule.

Field Summary

Fields

Modifier and Type	Field and Description
static int	COMPLEX_I Print Complex as 3+2 i
static int	FULL_BRACKET All brackets are printed.

Constructor Summary

Constructors

Constructor and Description
PrintVisitor() Creates a visitor to create and print string representations of an expression tree.

Method Summary

Modifier and Type	Method and Description
void	addSpecialRule(Operator op, PrintVisitor.PrintRulesI rules) Adds a special print rule to be added for a given operator.
void	append(String s) Add a string to buffer.
String	formatValue(Object val) Returns a formated version of the value.
void	formatValue(Object val, StringBuffer sb1) Appends a formatted versions of val to the string buffer.
int	getMaxLen()
int	getMode() Return the current print mode.
boolean	getMode(int testmode)
void	print(Node node) Prints on System.out.
void	print(Node node, PrintStream out) Prints the tree descending from node with lots of brackets or specified stream.
void	println(Node node) Prints on System.out.
void	println(Node node, PrintStream out) Prints the tree descending from node with a newline at end.
void	setMaxLen(int i) Sets the maximum length printed per line.
void	setMode(int mode, boolean flag) Set printing mode.
void	setNumberFormat(NumberFormat format)
String	toString(Node node) returns a String representation of the equation.
Object	visit(ASTConstant node, Object data)
Object	visit(ASTFunNode node, Object data)
Object	visit(ASTVarNode node, Object data)

Methods inherited from class org.lsmp.djep.xjep.ErrorCatchingVisitor

acceptCatchingErrors, addError, clearErrors, getError, getErrorsMessage, hasErrors

Methods inherited from class org.lsmp.djep.xjep.DoNothingVisitor

visit, visit

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

FULL_BRACKET

public static final int FULL_BRACKET

All brackets are printed. Removes all ambiguity.

See Also:

Constant Field Values

COMPLEX_I

public static final int COMPLEX_I

Print Complex as 3+2 i

See Also:

Constant Field Values

Constructor Detail

PrintVisitor

public PrintVisitor()

Creates a visitor to create and print string representations of an expression tree.

Method Detail

print

public void print(Node node,
                  PrintStream out)

Prints the tree descending from node with lots of brackets or specified stream.

See Also:

XJep.println(Node, PrintStream)

print

public void print(Node node)

Prints on System.out.

println

public void println(Node node,
                    PrintStream out)

Prints the tree descending from node with a newline at end.

println

public void println(Node node)

Prints on System.out.

toString

public String toString(Node node)

returns a String representation of the equation.

append

public void append(String s)

Add a string to buffer. Classes implementing PrintRulesI should call this add the

addSpecialRule

public void addSpecialRule(Operator op,
                           PrintVisitor.PrintRulesI rules)

Adds a special print rule to be added for a given operator. TODO Allow special rules for other functions, i.e. not operators.

visit

public Object visit(ASTFunNode node,
                    Object data)
             throws ParseException

Specified by:

visit in interface ParserVisitor

Overrides:

visit in class DoNothingVisitor

Throws:

ParseException

visit

public Object visit(ASTVarNode node,
                    Object data)
             throws ParseException

Specified by:

visit in interface ParserVisitor

Overrides:

visit in class DoNothingVisitor

Throws:

ParseException

visit

public Object visit(ASTConstant node,
                    Object data)

Specified by:

visit in interface ParserVisitor

Overrides:

visit in class DoNothingVisitor

formatValue

public void formatValue(Object val,
                        StringBuffer sb1)

Appends a formatted versions of val to the string buffer.

Parameters:

val - The value to format

sb1 - The StingBuffer to append to

formatValue

public String formatValue(Object val)

Returns a formated version of the value.

getMode

public int getMode()

Return the current print mode.

getMode

public boolean getMode(int testmode)

setMode

public void setMode(int mode,
                    boolean flag)

Set printing mode. In full bracket mode the brackets each element in the tree will be surrounded by brackets to indicate the tree structure. In the default mode, (full bracket off) the number of brackets is minimised so (x+y)+z will be printed as x+y+z.

Parameters:

mode - which flags to change, typically FULL_BRACKET

flag - whether to switch this mode on or off

setNumberFormat

public void setNumberFormat(NumberFormat format)

setMaxLen

public void setMaxLen(int i)

Sets the maximum length printed per line. If the value is not -1 then the string will be broken into chunks each of which is less than the max length.

Parameters:

i - the maximum length

getMaxLen

public int getMaxLen()

Returns:

the maximum length printed per line