*
* @author Achim Westermann
*
* @version $Revision: 1.10 $
*
* @see info.monitorenter.util.units.UnitFactory
*
* @see info.monitorenter.util.units.IUnitSystem
*
* @see info.monitorenter.util.units.UnitSystemSI
*/
public abstract class AUnit extends Object implements Serializable {
/** Generated serialVersionUID. **/
private static final long serialVersionUID = -8890511971185813347L;
/**
* @see java.lang.Object#hashCode()
*/
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result + this.m_decimals;
long temp;
temp = Double.doubleToLongBits(this.m_factor);
result = prime * result + (int) (temp ^ (temp >>> 32));
result = prime * result + ((this.m_unitName == null) ? 0 : this.m_unitName.hashCode());
return result;
}
/**
* @see java.lang.Object#equals(java.lang.Object)
*/
@Override
public boolean equals(Object obj) {
if (this == obj) {
return true;
}
if (obj == null) {
return false;
}
if (getClass() != obj.getClass()) {
return false;
}
AUnit other = (AUnit) obj;
if (this.m_decimals != other.m_decimals) {
return false;
}
if (Double.doubleToLongBits(this.m_factor) != Double.doubleToLongBits(other.m_factor)) {
return false;
}
if (this.m_unitName == null) {
if (other.m_unitName != null) {
return false;
}
} else if (!this.m_unitName.equals(other.m_unitName)) {
return false;
}
return true;
}
/** Decimals for rounding. */
protected int m_decimals = 2;
/**
* The factor a result of {@link #getValue(double)} had to be multiplied with
* if the real (unitless) value has to be calculated.
*/
protected double m_factor;
/**
* The next smaller unit to this one within this unit's {@link IUnitSystem}.
*
*/ protected AUnit m_nexLowerUnit; /** * The next greater unit to this one within this unit's {@link IUnitSystem}. *
*/ protected AUnit m_nextHigherUnit; /** * The short unit name of this unit a result of {@link #getValue(double)} has * to be related with to know the this result is displayed in a unit. *
*/ protected String m_unitName; /** * Protected constructor to ensure package access only. *
* * Use {@link UnitFactory#getInstance()} and * {@link UnitFactory#getUnit(double, IUnitSystem)} to obtain a proper unit. *
* */ protected AUnit() { // nop } /** * Returns the number of decimals that should be be taken into account if the * method {@link #getValue(double)} is invoked (rounding). *
* * @return the number of decimals that should be be taken into account if the * method {@link #getValue(double)} is invoked (rounding). */ public int getDecimals() { return this.m_decimals; } /** * Returns the factor a result of {@link #getValue(double)} had to be * multiplied with if the real (unitless) value has to be calculated. *
* * For performance reason (fast access) factor is public. This is against * "safety by desing" so do never set this value. *
* * @return the factor a result of {@link #getValue(double)} had to be * multiplied with if the real (unitless) value has to be calculated. */ public double getFactor() { return this.m_factor; } /** * Returns the the value divided by this unit's factor, rounded to this unit's * configured decimals and suffixed by the unit name. *
* * @param value * the value for the label. * * @return the the value divided by this unit's factor, rounded by this unit's * configured decimals and suffixed by the unit name. * * @see #getUnitName() * @see #getDecimals() * */ public String getLabel(final double value) { return new StringBuffer().append(this.round(value / this.m_factor)).append(" ").append( this.m_unitName).toString(); } /** * Returns the next smaller unit to this one within this unit's * {@link IUnitSystem}. *
*
* If this is already the smallest unit, this will be returned so add
* unit == unit.getLowerUnit() as the termination criteria in
* loops to search for the smallest unit (to avoid endless loops).
*
* * @return the next lower unit to this one within this unit's * {@link IUnitSystem}. */ public AUnit getNexLowerUnit() { return this.m_nexLowerUnit; } /** * Returns the next greater unit to this one within this unit's * {@link IUnitSystem}. *
*
* If this is already the greatest unit, this will be returned so add
* unit == unit.getNextHigherUnit() as the termination criteria
* in loops to search for the greatest unit (to avoid endless loops).
*
* * @return the next greater unit to this one within this unit's * {@link IUnitSystem}. */ public AUnit getNextHigherUnit() { return this.m_nextHigherUnit; } /** * Retunrns the short unit name of this unit a result of * {@link #getValue(double)} has to be related with to know the this result is * displayed in a unit. *
* * @return the short unit name of this unit a result of * {@link #getValue(double)} has to be related with to know the this * result is displayed in a unit. *
*/ public String getUnitName() { return this.m_unitName; } /** * Transforms the given absolute value into the represented unit value by * dividing by the specific factor. *
* * The result is rounded using the actual decimal setting. *
* * @param value * the value to represent in this unit. * * @return The value to display in this unit rounded using the internal * decimals. */ public double getValue(final double value) { return this.round(value / this.m_factor); } /** * Internal rounding routine for {@link #getValue(double)}. *
* * @param value * the value to round. * @return the given value rounded to the amount of decimals configured. */ private final double round(final double value) { double tmp = Math.pow(10, this.m_decimals); return (Math.floor(value * tmp + 0.5d)) / tmp; } /** * Define how many decimals should be taken into account if the method * {@link #getValue(double)} is invoked (rounding). *
* * @param aftercomma * the number of decimals that should be taken into account if the * method {@link #getValue(double)} is invoked (rounding) */ public void setDecimals(final int aftercomma) { if (aftercomma >= 0) { this.m_decimals = aftercomma; } } /** * Returns the same as {@link #getUnitName()}, prefer calling this directly * if desired. *
* * @return the same as {@link #getUnitName()}, prefer calling this directly * if desired. * */ @Override public String toString() { return this.getUnitName(); } }