sdouble.java

来自「OpenJMS是一个开源的Java Message Service API 1.」· Java 代码 · 共 198 行

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 * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED
 * OF THE POSSIBILITY OF SUCH DAMAGE.
 *
 * Copyright 2000,2001 (C) Exoffice Technologies Inc. All Rights Reserved.
 */

package org.exolab.jms.selector;


/**
 * This class is an adapter for the Double type.
 *
 * @version     $Revision: 1.1 $ $Date: 2004/11/26 01:50:44 $
 * @author      <a href="mailto:[e-mail]">Tim Anderson</a>
 * @see         SNumber
 */
final class SDouble extends SNumber {

    /**
     * The wrapped value
     */
    private final double _value;

    /**
     * Construct a new <code>SDouble</code>, initialised to <code>0</code>
     */
    public SDouble() {
        _value = 0;
    }

    /**
     * Construct a new <code>SDouble</code>
     *
     * @param value the underlying value
     */
    public SDouble(final double value) {
        _value = value;
    }

    /**
     * Returns the addition of a number to this
     *
     * @param number the number to add
     * @return the value of <code>this + number<code>
     */
    public SNumber add(final SNumber number) {
        return new SDouble(_value + number.getDouble());
    }

    /**
     * Returns the value of the substraction of a number from this
     *
     * @param number the number to subtract
     * @return the value of <code>this - number<code>
     */
    public SNumber subtract(final SNumber number) {
        return new SDouble(_value - number.getDouble());
    }

    /**
     * Returns the multiplication of a number to this
     *
     * @param number the number to multiply
     * @return the value of <code>this * number<code>
     */
    public SNumber multiply(final SNumber number) {
        return new SDouble(_value * number.getDouble());
    }

    /**
     * Returns the division of a number from this
     *
     * @param number the number to divide
     * @return the value of <code>this / number<code>
     */
    public SNumber divide(final SNumber number) {
        SNumber result = null;
        try {
            result = new SDouble(_value / number.getDouble());
        } catch (ArithmeticException ignore) {
        }
        return result;
    }

    /**
     * Returns the value of this as a <code>long</code>
     *
     * @return the value of this as a <code>long</code>
     */
    public long getLong() {
        return (long) _value;
    }

    /**
     * Returns the value of this as a <code>double</code>
     *
     * @return the value of this as a <code>double</code>
     */
    public double getDouble() {
        return _value;
    }

    /**
     * Returns the value of this, wrapped in a <code>Double</code>
     *
     * @return the value of this, wrapped in a <code>Double</code>
     */
    public Object getObject() {
        return new Double(_value);
    }

    /**
     * Determines if this is equal to another object.
     *
     * @param obj the object to compare. An instance of <code>SNumber</code>
     * @return <code>SBool.TRUE</code> if <code>this = obj</code>, otherwise
     * <code>SBool.FALSE</code>
     */
    public SBool equal(final SObject obj) {
        SBool result = SBool.FALSE;
        double rhs = ((SNumber) obj).getDouble();
        if (_value == rhs) {
            result = SBool.TRUE;
        }
        return result;
    }

    /**
     * Determines if this is less than another object.
     *
     * @param obj the object to compare. An instance of <code>SNumber</code>
     * @return <code>SBool.TRUE</code> if <code>this &lt; obj</code>, otherwise
     * <code>SBool.FALSE</code>
     */
    public SBool less(final SObject obj) {
        SBool result = SBool.FALSE;
        double rhs = ((SNumber) obj).getDouble();
        if (_value < rhs) {
            result = SBool.TRUE;
        }
        return result;
    }

    /**
     * Determines if this is greater than another object.
     *
     * @param obj the object to compare. An instance of <code>SNumber</code>
     * @return <code>SBool.TRUE</code> if <code>this &gt; obj</code>, otherwise
     * <code>SBool.FALSE</code>
     */
    public SBool greater(final SObject obj) {
        SBool result = SBool.FALSE;
        double rhs = ((SNumber) obj).getDouble();
        if (_value > rhs) {
            result = SBool.TRUE;
        }
        return result;
    }

} //-- SDouble