com.groiss.ds

Class StringExpression

java.lang.Object

com.groiss.ds.StringExpression

public abstract class StringExpression
extends Object

An expression is parsed, the containing variables are substituted with values. The caller calls the parse method with a string, the variables are handed over to an abstract varSubstitute method. The expression has the following form: { any-char* "{" placeholder ["," ("date" | "datetime" | decimal-format-mask ) ] "}" any_char* }*

Constructor Summary

Constructors

Constructor and Description
StringExpression()

Method Summary

Modifier and Type	Method and Description
protected void	appendIfNotEmpty(StringBuilder result, Object val) appends the given value. if the value is null/empty and the current result ends with a blank, this blank is removed to avoid accumulating blanks for optional values
String	parse(String s) Call this method to evaluate the expression.
abstract Object	varSubstitute(String s) Abstract method for var substitution, should be implemented by subclasses.

Methods inherited from class java.lang.Object

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

Constructor Detail

StringExpression

public StringExpression()

Method Detail

appendIfNotEmpty

protected final void appendIfNotEmpty(StringBuilder result,
                                      Object val)

appends the given value. if the value is null/empty and the current result ends with a blank, this blank is removed to avoid accumulating blanks for optional values

Parameters:

result -

val -

parse

public String parse(String s)

Call this method to evaluate the expression.

Parameters:

s - the expression

Returns:

the evaluated expression.

varSubstitute

public abstract Object varSubstitute(String s)

Abstract method for var substitution, should be implemented by subclasses.

Parameters:

s - the variable name

Returns:

the value