Java JEP.parseExpression方法代码示例

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
public void testClone3() {
    JEP jepExpression = new JEP();
    jepExpression.setAllowUndeclared(true);
    jepExpression.addStandardConstants();
    jepExpression.addStandardFunctions();

    jepExpression.parseExpression("append(a, b, c)");
    System.out.println("JEP: " + jepExpression);
    System.out.println(jepExpression.getTopNode().toLongString());
    jepExpression.setVarValue("a", "Uno");
    jepExpression.setVarValue("b", "Due");
    jepExpression.setVarValue("c", "Tre");
    System.out.println("Value: " + jepExpression.getValueAsObject());

    JEP clone = (JEP) jepExpression.clone();
    clone.setVarValue("a", "Dieci");
    clone.setVarValue("b", "Undici");
    clone.setVarValue("c", "Dodici");

    System.out.println("Value originale: " + jepExpression.getValueAsObject());
    System.out.println("Value clone: " + clone.getValueAsObject());

}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
public void test6() {
    JEP jepExpression = new JEP();
    jepExpression.setAllowUndeclared(true);
    jepExpression.addStandardConstants();
    jepExpression.addStandardFunctions();
    jepExpression.parseExpression("year > 1980");
    System.out.println("JEP: " + jepExpression);
    jepExpression.setVarValue("year", 1981);
    Object value1 = jepExpression.getValueAsObject();
    System.out.println("Value: " + value1);
    assertEquals(1.0, value1);
    jepExpression.setVarValue("year", 1971);
    Object value2 = jepExpression.getValueAsObject();
    System.out.println("Value: " + value2);
    assertEquals(0.0, value2);        
    jepExpression.setVarValue("year", "1971");
    System.out.println("Value: " + jepExpression.getValueAsObject());
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * 计算数学表达式
 * @param value
 * @return
 */
public static double formulaParser (String value){
	double sum = 0;
	JEP myParser = null;
	if(myParser==null){
		myParser = getJep();
	}
	try{
		myParser.parseExpression(value);
		boolean hasError = myParser.hasError();
		sum = myParser.getValue();
		
	}catch(Exception e){
		e.printStackTrace();
		
	}
	return sum;
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
public void testClonazione3() {
    JEP jepExpression = new JEP();
    jepExpression.setAllowUndeclared(true);
    jepExpression.addStandardConstants();
    jepExpression.addStandardFunctions();

    jepExpression.parseExpression("append(a, b, c)");
    System.out.println("JEP: " + jepExpression);
    System.out.println(jepExpression.getTopNode().toLongString());
    jepExpression.setVarValue("a", "Uno");
    jepExpression.setVarValue("b", "Due");
    jepExpression.setVarValue("c", "Tre");
    System.out.println("Value: " + jepExpression.getValueAsObject());

    JEP clone = (JEP) jepExpression.clone();
    clone.setVarValue("a", "Dieci");
    clone.setVarValue("b", "Undici");
    clone.setVarValue("c", "Dodici");

    System.out.println("Value originale: " + jepExpression.getValueAsObject());
    System.out.println("Value clone: " + clone.getValueAsObject());

}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
@Override
public void process(RegisterData data, String funcArg) {
	log.trace("Processing: "+funcArg);
	JEP j = new JEP();
	j.addStandardConstants();
	j.addStandardFunctions();
	j.addConstant("$", new Double(data.getFloat()));
	
	j.parseExpression(funcArg);
	
	if (j.hasError()) {
		log.error((j.getErrorInfo()));
		data.setNull();
	} else {
		Double value = j.getValue();
		
		if (j.hasError()) {
			log.error(j.getErrorInfo());
		} else {
			data.setDataFloat(value.floatValue());
			log.trace("Evaluated to : "+value);
		}
	}
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
@Override
public double getValue() throws CalcExeption {
	// If no formula is set, throw an exception.
	if(formula == null){
		throw new CalcFormulaNotSetException();
	}
	
	// JEP parser instance
	JEP parser = new JEP();
	parser.addStandardConstants();
	parser.addStandardFunctions();
	// Initiate parameters
	Iterator<String> params = parameters.keySet().iterator();
	while(params.hasNext()){
		String key = params.next();
		parser.addVariable(key, parameters.get(key).getValue());
	}
	
	// Set the expression to parse
	parser.parseExpression(formula);
	parser.getSymbolTable().toString();
	
	// Get the result
	double result = parser.getValue();
	if(Double.isNaN(result)){
		throw new CalcParameterNotSetException();
	}
	return result;
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Evaluates whether an expression is true or false.
 *
 * @param expression the expression to evaluate.
 * @return True if the expression is true, false otherwise.
 */
public static boolean expressionIsTrue( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );

    return isEqual( parser.getValue(), 1.0 );
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Calculates a regular mathematical expression.
 *
 * @param expression The expression to calculate.
 * @return The result of the operation.
 */
public static Object calculateGenericExpression( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );

    Object result = parser.getValueAsObject();

    return result;
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
private static double calculateExpressionInternal( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );

    return parser.getValue();
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Investigates whether the expression is valid or has errors.
 *
 * @param expression The expression to validate.
 * @return True if the expression has errors, false otherwise.
 */
public static boolean expressionHasErrors( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );

    return parser.hasError();
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Returns the error information for an invalid expression.
 *
 * @param expression The expression to validate.
 * @return The error information for an invalid expression, null if
 * the expression is valid.
 */
public static String getExpressionErrorInfo( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );

    return parser.getErrorInfo();
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Calculate the expression.
 * 
 * @param expression
 *            Expression string
 * @return calculate result
 * @throws IllegalArgumentException
 */
public static double calculateExpression(String expression) throws IllegalArgumentException {
	JEP myParser = new JEP();
	myParser.parseExpression(expression);

	if (myParser.hasError()) {
		throw new IllegalArgumentException();
	}

	return myParser.getValue();
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Evaluates whether an expression is true or false.
 * 
 * @param expression the expression to evaluate.
 * @return True if the expression is true, false otherwise.
 */
public static boolean expressionIsTrue( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );
    
    return isEqual( parser.getValue(), 1.0 );
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
private static double calculateExpressionInternal( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );
    
    return parser.getValue();
}
 

import org.nfunk.jep.JEP; //导入方法依赖的package包/类
/**
 * Investigates whether the expression is valid or has errors.
 * 
 * @param expression The expression to validate.
 * @return True if the expression has errors, false otherwise.
 */
public static boolean expressionHasErrors( String expression )
{
    final JEP parser = getJep();
    parser.parseExpression( expression );
    
    return parser.hasError();
}