get.java

JAVA 数学程序库 提供常规的数值计算程序包

package jmathlib.toolbox.jmathlib.graphics;

import jmathlib.core.tokens.*;
import jmathlib.core.tokens.numbertokens.DoubleNumberToken;
import jmathlib.core.functions.ExternalFunction;
import jmathlib.core.graphics.*;
import java.awt.Color;

public class get extends ExternalFunction
{

	public OperandToken evaluate(Token[] operands)
	{


        double x=0;
        
        if (getNArgIn(operands) > 2)
			throwMathLibException("get: number of arguments >2");

        if (getNArgIn(operands) >= 1)
        {
            if (!(operands[0] instanceof DoubleNumberToken)) 
            throwMathLibException("get: argument must be a number");

            x = ((DoubleNumberToken)operands[0]).getValueRe();
        }
        
        
        HandleObject ho = null;
        
        try {
            ho = HandleObject.getHandleObject((int)x);
        }
        catch (Exception e)
        {
            
        }
        
        //HandleObject.listObjects();
        
        
        if (getNArgIn(operands) == 1)
        {
            // e.g. get(1234)
            getInterpreter().displayText("");
            ho.show(getInterpreter());
            return null;
        }
        else if (getNArgIn(operands) == 2)
        {
            // e.g. get(1234, 'Children')
            if (!(operands[1] instanceof CharToken)) 
            throwMathLibException("get: second argument must be a string");

            String prop = ((CharToken)operands[1]).toString();
            
            Object obj = null;
            try {
                obj = HandleObject.getHandleObject((int)x).getProperty(prop).get();
            }
            catch (Exception e)
            {
               e.printStackTrace();
            }
            
            if (obj instanceof Boolean)
            {
                boolean b = ((Boolean)obj).booleanValue();

                if (b)
                    return new DoubleNumberToken( 1 );
                else
                    return new DoubleNumberToken( 0 );
            }
            else if (obj instanceof String)
            {
                return new CharToken ( ((String)obj).toString() ); 
            }
            else if (obj instanceof Number)
            {
                return new DoubleNumberToken ( ((Number)obj).intValue() ); 
            }
            else if (obj instanceof double[])
            {
                double[] d = ((double[])obj);
                
                return new DoubleNumberToken ( new double[][] {d} ); 
            }
            else if (obj instanceof double[][])
            {
                double[][] d = ((double[][])obj);
                
                return new DoubleNumberToken ( d ); 
            }
            else if (obj instanceof Color)
            {
                Color c = ((Color)obj);
                
                double[] d = new double[3];
                d[0] = (double)c.getRed()/255.0;
                d[1] = (double)c.getGreen()/255.0;
                d[2] = (double)c.getBlue()/255.0;
                return new DoubleNumberToken ( new double[][] {d} ); 
            }
            else
                throwMathLibException("get: unknown return value ");
                
            
        }
        
		return null;
	}
}

/*
@GROUP
graphics
@SYNTAX
get
@DOC
.
@EXAMPLES
.
@NOTES
@SEE
set, plot
*/