Java tutorial
/* This file is part of Cyclos (www.cyclos.org). A project of the Social Trade Organisation (www.socialtrade.org). Cyclos is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version. Cyclos is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with Cyclos; if not, write to the Free Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111-1307 USA */ package nl.strohalm.cyclos.utils; import java.io.Serializable; import nl.strohalm.cyclos.utils.validation.MaxLengthError; import nl.strohalm.cyclos.utils.validation.MinLengthError; import nl.strohalm.cyclos.utils.validation.ValidationError; import org.apache.commons.lang.builder.EqualsBuilder; import org.apache.commons.lang.builder.HashCodeBuilder; /** * Contains a range constraint * @author luis */ public class RangeConstraint implements Serializable, Cloneable { private static final long serialVersionUID = -7227958658299214274L; /** * Returns a range from min to max */ public static RangeConstraint between(final int min, final int max) { return new RangeConstraint(min, max); } /** * Returns a range from and to the parameter */ public static RangeConstraint fixed(final int length) { return new RangeConstraint(length, length); } /** * Returns a range from min with no max */ public static RangeConstraint from(final int min) { return new RangeConstraint(min, null); } /** * Returns a range from to max with no min */ public static RangeConstraint to(final int max) { return new RangeConstraint(null, max); } private Integer max; private Integer min; public RangeConstraint() { } public RangeConstraint(final Integer min, final Integer max) { this.min = min; this.max = max; } @Override public RangeConstraint clone() { try { return (RangeConstraint) super.clone(); } catch (final CloneNotSupportedException e) { return null; } } @Override public boolean equals(final Object obj) { if (!(obj instanceof RangeConstraint)) { return false; } final RangeConstraint rc = (RangeConstraint) obj; return new EqualsBuilder().append(min, rc.min).append(max, rc.max).isEquals(); } /** * Return a validation error if the number is out of range, or null if ok */ public ValidationError errorFor(final int number) { if (min != null && min > 0 && number < min) { return new MinLengthError(min); } if (max != null && max > 0 && number > max) { return new MaxLengthError(max); } return null; } public Integer getMax() { return max; } public Integer getMin() { return min; } @Override public int hashCode() { return new HashCodeBuilder().append(min).append(max).toHashCode(); } /** * Check if the given number is in range */ public boolean inRange(final int number) { if (min != null && min < number) { return false; } if (max != null && max > number) { return false; } return true; } public void setMax(final Integer max) { this.max = max; } public void setMin(final Integer min) { this.min = min; } @Override public String toString() { return min + " - " + max; } }