Sample.java

/*******************************************************************************
 * Copyright (c) 2010 Oak Ridge National Laboratory.
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * http://www.eclipse.org/legal/epl-v10.html
 ******************************************************************************/
package org.csstudio.swt.xygraph.dataprovider;

/** An (x,y) sample data with error.
 *  <p>
 *  The error values are absolute, positive numbers.
 *  For example, a Sample with Y=5, negative Y error 1 and positive Y error 2
 *  represents a number of 5 that could also be anywhere in 4 .. 7.
 *  The errors are not percentages.
 *  The 'negative' error is actually a positive number.
 *  <p>
 *  Note:
 *  Only the x/y value is used in equals()!
 *  Error ranges and info texts are ignored when determining equality
 *  with another Sample.
 *  
 *  @author Xihui Chen
 *  @author Kay Kasemir Comments, made immutable
 */
public class Sample implements ISample {
    final private double xValue;
    final private double yValue;
    final private double xPlusError;
    final private double yPlusError;
    final private double xMinusError;
    final private double yMinusError;
    final private String info;
	
	/** Initialize with x/y value
	 *  @param xdata
	 *  @param ydata
	 */
	public Sample(final double xdata, final double ydata) {
	    this(xdata, ydata, 0, 0, 0, 0, ""); //$NON-NLS-1$
	}

   /** Initialize with value and error range
    *  @param xValue
    *  @param yValue
    *  @param yPlusError
    *  @param yMinusError
    *  @param xPlusError
    *  @param xMinusError
    */
    public Sample(final double xValue, final double yValue,
            final double yPlusError, final double yMinusError, 
            final double xPlusError, final double xMinusError) {
       this(xValue, yValue, yPlusError, yMinusError,
           xPlusError, xMinusError,  ""); //$NON-NLS-1$
    }

    /** Initialize with value, error ranges and info text
     *  @param xValue
     *  @param yValue
     *  @param yPlusError
     *  @param yMinusError
     *  @param xPlusError
     *  @param xMinusError
     *  @param info
     */
	public Sample(final double xValue, final double yValue,
	        final double yPlusError, final double yMinusError, 
	        final double xPlusError, final double xMinusError,
	        final String info) {
		this.xValue = xValue;
		this.yValue = yValue;
		this.xPlusError = xPlusError;
		this.yPlusError = yPlusError;
		this.xMinusError = xMinusError;
		this.yMinusError = yMinusError;
		this.info = info;
	}

	/** @return X value */
	@Override
	public double getXValue() {
    	return xValue;
    }

    /** @return Y value */
    @Override
	public double getYValue() {
    	return yValue;
    }

    /** @return Negative X error. */
    @Override
	public double getXMinusError() {
		return xMinusError;
	}
    
    /** @return Positive X error. */
	@Override
	public double getXPlusError() {
		return xPlusError;
	}
	
    /** @return Negative Y error. */
	@Override
	public double getYMinusError() {
		return yMinusError;
	}

    /** @return Positive Y error. */
	@Override
	public double getYPlusError() {
		return yPlusError;
	}

    /** @return Sample info text. */
	@Override
	public String getInfo() {
		return info;
	}
	
	

//    @Override
//    public boolean equals(final Object obj) {
//    	if(obj instanceof Sample)
//    		return  (((Sample)obj).xValue == xValue && ((Sample)obj).yValue == yValue);
//    	return false;
//    }

    @Override
	public int hashCode() {
		final int prime = 31;
		int result = 1;
		result = prime * result + ((info == null) ? 0 : info.hashCode());
		long temp;
		temp = Double.doubleToLongBits(xMinusError);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(xPlusError);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(xValue);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(yMinusError);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(yPlusError);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		temp = Double.doubleToLongBits(yValue);
		result = prime * result + (int) (temp ^ (temp >>> 32));
		return result;
	}

	@Override
	public boolean equals(Object obj) {
		if (this == obj)
			return true;
		if (obj == null)
			return false;
		if (getClass() != obj.getClass())
			return false;
		Sample other = (Sample) obj;
		if (info == null) {
			if (other.info != null)
				return false;
		} else if (!info.equals(other.info))
			return false;
		if (Double.doubleToLongBits(xMinusError) != Double
				.doubleToLongBits(other.xMinusError))
			return false;
		if (Double.doubleToLongBits(xPlusError) != Double
				.doubleToLongBits(other.xPlusError))
			return false;
		if (Double.doubleToLongBits(xValue) != Double
				.doubleToLongBits(other.xValue))
			return false;
		if (Double.doubleToLongBits(yMinusError) != Double
				.doubleToLongBits(other.yMinusError))
			return false;
		if (Double.doubleToLongBits(yPlusError) != Double
				.doubleToLongBits(other.yPlusError))
			return false;
		if (Double.doubleToLongBits(yValue) != Double
				.doubleToLongBits(other.yValue))
			return false;
		return true;
	}

	/** @return String representation, mostly for debugging */
    @SuppressWarnings("nls")
    @Override
    public String toString() {
        final StringBuilder buf = new StringBuilder();
        buf.append("(");
        buf.append(xValue);
        if (xMinusError != 0  ||  xPlusError != 0)
            buf.append(" [-" + xMinusError + " ... +" + xPlusError + "]");
        buf.append(", ");
        buf.append(yValue);
        if (yMinusError != 0  ||  yPlusError != 0)
            buf.append(" [-" + yMinusError + " ... +" + yPlusError + "]");
        if (info != null  &&  info.length() > 0)
            buf.append(", '" + info + "'");
        buf.append(")");
        return buf.toString();
    }
}