1 /*
2 * ModeShape (http://www.modeshape.org)
3 * See the COPYRIGHT.txt file distributed with this work for information
4 * regarding copyright ownership. Some portions may be licensed
5 * to Red Hat, Inc. under one or more contributor license agreements.
6 * See the AUTHORS.txt file in the distribution for a full listing of
7 * individual contributors.
8 *
9 * ModeShape is free software. Unless otherwise indicated, all code in ModeShape
10 * is licensed to you under the terms of the GNU Lesser General Public License as
11 * published by the Free Software Foundation; either version 2.1 of
12 * the License, or (at your option) any later version.
13 *
14 * ModeShape is distributed in the hope that it will be useful,
15 * but WITHOUT ANY WARRANTY; without even the implied warranty of
16 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
17 * Lesser General Public License for more details.
18 *
19 * You should have received a copy of the GNU Lesser General Public
20 * License along with this software; if not, write to the Free
21 * Software Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
22 * 02110-1301 USA, or see the FSF site: http://www.fsf.org.
23 */
24 package org.modeshape.graph.query.parse;
25
26 import net.jcip.annotations.Immutable;
27 import org.modeshape.common.text.Position;
28 import org.modeshape.common.util.CheckArg;
29 import org.modeshape.common.util.ObjectUtil;
30 import org.modeshape.graph.query.model.SelectorName;
31
32 /**
33 * A representation of a column as expressed in the SQL query. Note that the selector name may not have been explicitly specified.
34 */
35 @Immutable
36 class ColumnExpression {
37
38 private final SelectorName selectorName;
39 private final String propertyName;
40 private final String columnName;
41 private final Position position;
42
43 /**
44 * A column with the given name representing the named property on the node identified by the selector.
45 *
46 * @param selectorName the selector name; may be null if no selector was explicitly used in the query
47 * @param propertyName the name of the property
48 * @param columnName the name of the column
49 * @param position the position of the column in the query
50 */
51 ColumnExpression( SelectorName selectorName,
52 String propertyName,
53 String columnName,
54 Position position ) {
55 CheckArg.isNotNull(propertyName, "propertyName");
56 CheckArg.isNotNull(columnName, "columnName");
57 CheckArg.isNotNull(position, "position");
58 this.selectorName = selectorName;
59 this.propertyName = propertyName;
60 this.columnName = columnName;
61 this.position = position;
62 }
63
64 /**
65 * Get the column's position in the query.
66 *
67 * @return the column's position; never null
68 */
69 public Position getPosition() {
70 return position;
71 }
72
73 /**
74 * @return the name of the selector; may be null if no selector was explicitly used in the query
75 */
76 public final SelectorName getSelectorName() {
77 return selectorName;
78 }
79
80 /**
81 * @return propertyName
82 */
83 public final String getPropertyName() {
84 return propertyName;
85 }
86
87 /**
88 * @return columnName
89 */
90 public final String getColumnName() {
91 return columnName;
92 }
93
94 /**
95 * {@inheritDoc}
96 *
97 * @see java.lang.Object#equals(java.lang.Object)
98 */
99 @Override
100 public boolean equals( Object obj ) {
101 if (obj == this) return true;
102 if (obj instanceof ColumnExpression) {
103 ColumnExpression that = (ColumnExpression)obj;
104 if (!ObjectUtil.isEqualWithNulls(this.selectorName, that.selectorName)) return false;
105 if (!ObjectUtil.isEqualWithNulls(this.propertyName, that.propertyName)) return false;
106 if (!ObjectUtil.isEqualWithNulls(this.columnName, that.columnName)) return false;
107 return true;
108 }
109 return false;
110 }
111
112 /**
113 * {@inheritDoc}
114 *
115 * @see java.lang.Object#toString()
116 */
117 @Override
118 public String toString() {
119 StringBuilder sb = new StringBuilder();
120 if (selectorName != null) {
121 sb.append(selectorName.name());
122 sb.append('.');
123 }
124 sb.append(propertyName);
125 if (columnName != null) {
126 sb.append(" AS ").append(columnName);
127 }
128 return sb.toString();
129 }
130 }