| 1 | /* This file is part of the project "Hilbert II" - http://www.qedeq.org |
| 2 | * |
| 3 | * Copyright 2000-2014, Michael Meyling <mime@qedeq.org>. |
| 4 | * |
| 5 | * "Hilbert II" is free software; you can redistribute |
| 6 | * it and/or modify it under the terms of the GNU General Public |
| 7 | * License as published by the Free Software Foundation; either |
| 8 | * version 2 of the License, or (at your option) any later version. |
| 9 | * |
| 10 | * This program is distributed in the hope that it will be useful, |
| 11 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 12 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 13 | * GNU General Public License for more details. |
| 14 | */ |
| 15 | |
| 16 | package org.qedeq.kernel.bo.logic.model; |
| 17 | |
| 18 | import org.qedeq.base.trace.Trace; |
| 19 | import org.qedeq.base.utility.StringUtility; |
| 20 | |
| 21 | /** |
| 22 | * One predicate for our model. |
| 23 | * |
| 24 | * @author Michael Meyling |
| 25 | */ |
| 26 | public abstract class Predicate { |
| 27 | |
| 28 | /** This class. */ |
| 29 | private static final Class CLASS = Predicate.class; |
| 30 | |
| 31 | /** Minimum number of arguments this predicate has. */ |
| 32 | private final int minimum; |
| 33 | |
| 34 | /** Maximum number of arguments this predicate has. */ |
| 35 | private final int maximum; |
| 36 | |
| 37 | /** Display text. */ |
| 38 | private final String display; |
| 39 | |
| 40 | /** Description for this predicate. */ |
| 41 | private final String description; |
| 42 | |
| 43 | /** |
| 44 | * Constructor. |
| 45 | * |
| 46 | * @param minimum Minimum number of arguments this predicate has. |
| 47 | * @param maximum Maximum number of arguments this predicate has. |
| 48 | * @param display Show this to represent the predicate within outputs. |
| 49 | * @param description Description for this predicate. |
| 50 | */ |
| 51 | public Predicate(final int minimum, final int maximum, final String display, |
| 52 | final String description) { |
| 53 | this.minimum = minimum; |
| 54 | this.maximum = maximum; |
| 55 | this.display = display; |
| 56 | this.description = description; |
| 57 | } |
| 58 | |
| 59 | /** |
| 60 | * Construct negation of other predicate. |
| 61 | * |
| 62 | * @param predicate Negate this predicate. |
| 63 | * @return Negation of predicate. |
| 64 | */ |
| 65 | public static Predicate not(final Predicate predicate) { |
| 66 | return new Predicate(predicate.getMinimumArgumentNumber(), |
| 67 | predicate.getMaximumArgumentNumber(), "!" + predicate.toString(), |
| 68 | "!" + predicate.getDescription()) { |
| 69 | public boolean calculate(final Entity[] entities) { |
| 70 | final String method = "not.calculate(Entity[])"; |
| 71 | if (Trace.isDebugEnabled(CLASS)) { |
| 72 | Trace.param(CLASS, method, "toString", toString()); |
| 73 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 74 | } |
| 75 | final boolean result = !predicate.calculate(entities); |
| 76 | Trace.param(CLASS, method, "result ", result); |
| 77 | return result; |
| 78 | } |
| 79 | }; |
| 80 | } |
| 81 | |
| 82 | /** |
| 83 | * Construct conjunction of two predicates. |
| 84 | * |
| 85 | * @param op1 First predicate. |
| 86 | * @param op2 Second predicate. |
| 87 | * @return Conjunction of two predicates. |
| 88 | */ |
| 89 | public static Predicate and(final Predicate op1, final Predicate op2) { |
| 90 | if (op1.getMinimumArgumentNumber() > op2.getMaximumArgumentNumber() |
| 91 | || op1.getMaximumArgumentNumber() < op2.getMinimumArgumentNumber()) { |
| 92 | throw new IllegalArgumentException("Predicates can not be combined " + op1 + " and " |
| 93 | + op2); |
| 94 | } |
| 95 | return new Predicate(Math.max(op1.getMinimumArgumentNumber(), |
| 96 | op2.getMinimumArgumentNumber()), Math.min(op1.getMaximumArgumentNumber(), |
| 97 | op2.getMaximumArgumentNumber()), op1.toString() + " and " + op2.toString(), |
| 98 | op1.getDescription() + " and " + op2.getDescription()) { |
| 99 | public boolean calculate(final Entity[] entities) { |
| 100 | final String method = "and.calculate(Entity[])"; |
| 101 | if (Trace.isDebugEnabled(CLASS)) { |
| 102 | Trace.param(CLASS, method, "toString", toString()); |
| 103 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 104 | } |
| 105 | boolean result = op1.calculate(entities) && op2.calculate(entities); |
| 106 | Trace.param(CLASS, method, "result ", result); |
| 107 | return result; |
| 108 | } |
| 109 | }; |
| 110 | } |
| 111 | |
| 112 | /** |
| 113 | * Construct disjunction of two predicates. |
| 114 | * |
| 115 | * @param op1 First predicate. |
| 116 | * @param op2 Second predicate. |
| 117 | * @return Disjunction of two predicates. |
| 118 | */ |
| 119 | public static Predicate or(final Predicate op1, final Predicate op2) { |
| 120 | if (op1.getMinimumArgumentNumber() > op2.getMaximumArgumentNumber() |
| 121 | || op1.getMaximumArgumentNumber() < op2.getMinimumArgumentNumber()) { |
| 122 | throw new IllegalArgumentException("Predicates can not be combined " + op1 + " and " |
| 123 | + op2); |
| 124 | } |
| 125 | return new Predicate(Math.max(op1.getMinimumArgumentNumber(), |
| 126 | op2.getMinimumArgumentNumber()), Math.min(op1.getMaximumArgumentNumber(), |
| 127 | op2.getMaximumArgumentNumber()), op1.toString() + " or " + op2.toString(), |
| 128 | op1.getDescription() + " or " + op2.getDescription()) { |
| 129 | public boolean calculate(final Entity[] entities) { |
| 130 | final String method = "or.calculate(Entity[])"; |
| 131 | if (Trace.isDebugEnabled(CLASS)) { |
| 132 | Trace.param(CLASS, method, "toString", toString()); |
| 133 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 134 | } |
| 135 | if (Trace.isDebugEnabled(CLASS)) { |
| 136 | Trace.param(CLASS, method, "toString", toString()); |
| 137 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 138 | } |
| 139 | boolean result = op1.calculate(entities) || op2.calculate(entities); |
| 140 | Trace.param(CLASS, method, "result ", result); |
| 141 | return result; |
| 142 | } |
| 143 | }; |
| 144 | } |
| 145 | |
| 146 | /** |
| 147 | * Construct identifying predicate. |
| 148 | * |
| 149 | * @param entity Check if all entities are equal to this. |
| 150 | * @return Predicate to check for this entity. |
| 151 | */ |
| 152 | public static Predicate isEntity(final Entity entity) { |
| 153 | return new Predicate(1, 99, "=" + entity, "= " + entity.getDescription()) { |
| 154 | public boolean calculate(final Entity[] entities) { |
| 155 | final String method = "isEntity.calculate(Entity[])"; |
| 156 | if (Trace.isDebugEnabled(CLASS)) { |
| 157 | Trace.param(CLASS, method, "toString", toString()); |
| 158 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 159 | } |
| 160 | if (Trace.isDebugEnabled(CLASS)) { |
| 161 | Trace.param(CLASS, method, "toString", toString()); |
| 162 | Trace.param(CLASS, method, "entities", StringUtility.toString(entities)); |
| 163 | } |
| 164 | boolean result = true; |
| 165 | for (int i = 0; i < entities.length; i++) { |
| 166 | result &= entity.getValue() == entities[i].getValue(); |
| 167 | } |
| 168 | Trace.param(CLASS, method, "result ", result); |
| 169 | return result; |
| 170 | } |
| 171 | }; |
| 172 | } |
| 173 | |
| 174 | /** |
| 175 | * Get minimum number of arguments this predicate has. |
| 176 | * |
| 177 | * @return Minimum number of arguments for this predicate. |
| 178 | */ |
| 179 | public int getMinimumArgumentNumber() { |
| 180 | return minimum; |
| 181 | } |
| 182 | |
| 183 | /** |
| 184 | * Get maximum number of arguments this predicate has. |
| 185 | * |
| 186 | * @return Maximum umber of arguments for this predicate. |
| 187 | */ |
| 188 | public int getMaximumArgumentNumber() { |
| 189 | return maximum; |
| 190 | } |
| 191 | |
| 192 | /** |
| 193 | * Get display text. |
| 194 | * |
| 195 | * @return Representation of this predicate for textual output. |
| 196 | */ |
| 197 | public String toString() { |
| 198 | return display; |
| 199 | } |
| 200 | |
| 201 | /** |
| 202 | * Get description. |
| 203 | * |
| 204 | * @return Description of this predicate. |
| 205 | */ |
| 206 | public String getDescription() { |
| 207 | return description; |
| 208 | } |
| 209 | |
| 210 | /** |
| 211 | * Calculate truth value. |
| 212 | * |
| 213 | * @param entities Calculate predicate for this entities. |
| 214 | * @return Truth value. |
| 215 | */ |
| 216 | public abstract boolean calculate(Entity[] entities); |
| 217 | |
| 218 | } |