| 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.parser; |
| 17 | |
| 18 | import java.util.ArrayList; |
| 19 | import java.util.List; |
| 20 | |
| 21 | import org.qedeq.base.trace.Trace; |
| 22 | import org.qedeq.base.utility.StringUtility; |
| 23 | |
| 24 | /** |
| 25 | * Parsed term. |
| 26 | * |
| 27 | * @version $Revision: 1.1 $ |
| 28 | * @author Michael Meyling |
| 29 | */ |
| 30 | public class Term { |
| 31 | |
| 32 | /** This class. */ |
| 33 | private static final Class CLASS = Term.class; |
| 34 | |
| 35 | /** Operator, can be <code>null</code>. */ |
| 36 | private final Operator operator; |
| 37 | |
| 38 | /** Arguments, can be <code>null</code>. */ |
| 39 | private final List arguments; |
| 40 | |
| 41 | /** Atom, can be <code>null</code>. */ |
| 42 | private final TermAtom atom; |
| 43 | |
| 44 | /** |
| 45 | * Constructor. |
| 46 | * |
| 47 | * @param atom Term atom. |
| 48 | */ |
| 49 | public Term(final TermAtom atom) { |
| 50 | this.operator = null; |
| 51 | this.arguments = null; |
| 52 | this.atom = atom; |
| 53 | } |
| 54 | |
| 55 | |
| 56 | /** |
| 57 | * Constructor. |
| 58 | * |
| 59 | * @param operator Construct new term for this operator. |
| 60 | */ |
| 61 | public Term(final Operator operator) { |
| 62 | this.operator = operator; |
| 63 | this.arguments = new ArrayList(); |
| 64 | this.atom = null; |
| 65 | } |
| 66 | |
| 67 | /** |
| 68 | * Constructor. |
| 69 | * |
| 70 | * @param operator Construct new term for this operator. |
| 71 | * @param firstArgument First argument of operator. |
| 72 | */ |
| 73 | public Term(final Operator operator, final Term firstArgument) { |
| 74 | this.operator = operator; |
| 75 | this.arguments = new ArrayList(); |
| 76 | this.atom = null; |
| 77 | addArgument(firstArgument); |
| 78 | } |
| 79 | |
| 80 | /** |
| 81 | * Is this term an atom? |
| 82 | * |
| 83 | * @return Is this term an atom? |
| 84 | */ |
| 85 | public final boolean isAtom() { |
| 86 | return atom != null; |
| 87 | } |
| 88 | |
| 89 | /** |
| 90 | * Add next argument term to operator. Overall number of arguments must |
| 91 | * not exceed {@link Operator#getMax()} (if <code>>= 0</code>). Addition is only possible if |
| 92 | * this is no atom term (see {@link #Term(TermAtom)}). |
| 93 | * |
| 94 | * @param term Add this argument at last position. |
| 95 | * @throws IllegalArgumentException This is an atom term or argument |
| 96 | * maximum exceeded. |
| 97 | */ |
| 98 | public final void addArgument(final Term term) { |
| 99 | if (isAtom()) { |
| 100 | throw new IllegalArgumentException( |
| 101 | "this is an atom, no arguments could be added to " + atom.getValue()); |
| 102 | } |
| 103 | if (operator.getMax() >= 0 && operator.getMax() < arguments.size() + 1) { |
| 104 | throw new IllegalArgumentException("operator could have maximal " |
| 105 | + operator.getMax() + " arguments"); |
| 106 | } |
| 107 | arguments.add(term); |
| 108 | } |
| 109 | |
| 110 | /** |
| 111 | * Get operator of term. Can be <code>null</code> if this is an atom term. |
| 112 | * |
| 113 | * @return Term operator. |
| 114 | */ |
| 115 | public final Operator getOperator() { |
| 116 | return operator; |
| 117 | } |
| 118 | |
| 119 | /** |
| 120 | * Get number of arguments of this operator. |
| 121 | * |
| 122 | * @return Argument number. |
| 123 | */ |
| 124 | public final int size() { |
| 125 | if (arguments == null) { |
| 126 | return 0; |
| 127 | } |
| 128 | return arguments.size(); |
| 129 | } |
| 130 | |
| 131 | /** |
| 132 | * Get QEDEQ representation of this term. |
| 133 | * |
| 134 | * @return QEDEQ representation. |
| 135 | */ |
| 136 | public final String getQedeq() { |
| 137 | if (isAtom()) { |
| 138 | return atom.getValue(); |
| 139 | } |
| 140 | final StringBuffer buffer = new StringBuffer(); |
| 141 | buffer.append(operator.getQedeq()).append('('); |
| 142 | if (operator.getQedeqArgument() != null) { |
| 143 | buffer.append(StringUtility.quote(operator.getQedeqArgument())); |
| 144 | } |
| 145 | for (int i = 0; i < arguments.size(); i++) { |
| 146 | if (i > 0 || operator.getQedeqArgument() != null) { |
| 147 | buffer.append(", "); |
| 148 | } |
| 149 | buffer.append(((Term) |
| 150 | arguments.get(i)).getQedeq()); |
| 151 | } |
| 152 | buffer.append(')'); |
| 153 | return buffer.toString(); |
| 154 | } |
| 155 | |
| 156 | /** |
| 157 | * Get QEDEQ XML representation of this term. |
| 158 | * |
| 159 | * @return QEDEQ XML representation. |
| 160 | */ |
| 161 | public final String getQedeqXml() { |
| 162 | return getQedeqXml(0); |
| 163 | } |
| 164 | |
| 165 | /** |
| 166 | * Get QEDEQ XML representation of this term. |
| 167 | * |
| 168 | * @param level Tabulation level. |
| 169 | * @return QEDEQ XML representation. |
| 170 | */ |
| 171 | private final String getQedeqXml(final int level) { |
| 172 | if (isAtom()) { |
| 173 | return StringUtility.getSpaces(level * 2) + atom.getValue() + "\n"; |
| 174 | } |
| 175 | final StringBuffer buffer = new StringBuffer(); |
| 176 | buffer.append(StringUtility.getSpaces(level * 2)); |
| 177 | buffer.append("<").append(operator.getQedeq()); |
| 178 | if (operator.getQedeq().endsWith("VAR")) { // TODO mime 20060612: ok for all QEDEQ? |
| 179 | buffer.append(" id=" + quote(operator.getQedeqArgument())); |
| 180 | if (arguments == null || arguments.size() == 0) { |
| 181 | buffer.append(" />" + "\n"); |
| 182 | return buffer.toString(); |
| 183 | } |
| 184 | } else if (operator.getQedeq().endsWith("CON")) { |
| 185 | buffer.append(" ref=" + quote(operator.getQedeqArgument())); |
| 186 | if (arguments == null || arguments.size() == 0) { |
| 187 | buffer.append(" />" + "\n"); |
| 188 | return buffer.toString(); |
| 189 | } |
| 190 | } |
| 191 | |
| 192 | buffer.append(">\n"); |
| 193 | if (operator.getQedeqArgument() != null && !operator.getQedeq().endsWith("VAR") |
| 194 | && !operator.getQedeq().endsWith("CON")) { |
| 195 | // no arguments expected! |
| 196 | Trace.fatal(CLASS, this, "getQedeqXml(int)", "operator argument is not null but: " |
| 197 | + operator.getQedeqArgument(), new IllegalArgumentException()); |
| 198 | } |
| 199 | for (int i = 0; i < arguments.size(); i++) { |
| 200 | buffer.append(((Term) |
| 201 | arguments.get(i)).getQedeqXml(level + 1)); |
| 202 | } |
| 203 | buffer.append(StringUtility.getSpaces(level * 2)); |
| 204 | buffer.append("</").append(operator.getQedeq()).append(">\n"); |
| 205 | return buffer.toString(); |
| 206 | } |
| 207 | |
| 208 | /** |
| 209 | * Quote attribute value. |
| 210 | * |
| 211 | * @param text Attribute text. |
| 212 | * @return Quoted attribute. |
| 213 | */ |
| 214 | private String quote(final String text) { |
| 215 | return "\"" + StringUtility.replace(text, "\"", """) + "\""; |
| 216 | } |
| 217 | |
| 218 | } |