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1 package com.quadcap.sql;
2
3
40
41 import java.io.Externalizable  ;
42 import java.io.IOException ;
43 import java.io.ObjectInput ;
44 import java.io.ObjectOutput ;
45
46 import java.util.Vector ;
47
48 import java.sql.SQLException ;
49
50 import com.quadcap.sql.types.Op;
51 import com.quadcap.sql.types.Type;
52 import com.quadcap.sql.types.TypeBoolean;
53 import com.quadcap.sql.types.Value;
54 import com.quadcap.sql.types.ValueBoolean;
55
56 import com.quadcap.util.Debug;
57
58
63 public class QuantifiedCompare extends Expression implements Externalizable {
64 Expression e = null;
65 int op = 0;
66 int quant = 0;
67 Expression q = null;
68 boolean not = false;
69 ValueBoolean value = null;
70
71 public QuantifiedCompare() {}
72
73 public QuantifiedCompare(Expression e, int op, int quant, Expression q) {
74 this.e = e;
75 this.op = op;
76 this.quant = quant;
77 this.q = q;
78 }
79
80 public int rank() { return 1; }
81
82 public void invert() { not = !not; }
83
84 static boolean compare(int op, Row a, Row b) throws SQLException {
85 boolean eq = true;
86 for (int i = 1; eq && i <= a.size(); i++) {
87 Value va = a.item(i);
88 Value vb = b.item(i);
89 eq = Value.boolOp(op, va, vb);
90 }
91 return eq;
92 }
93
94 public Type getType(Session session, Cursor cursor) {
95 return TypeBoolean.typeBoolean;
96 }
97
98 public Value getValue(Session session, Cursor cursor)
99 throws SQLException
100 {
101 Cursor qcursor = q.getCursor(session, cursor);
102 try {
103 Row row = e.getValues(session, cursor);
104 boolean res = false;
105
106 if (quant == Op.ALL) {
107 res = true;
108 while (res && qcursor.next()) {
109 Row crow = qcursor.getRow();
110 res = compare(op, row, crow);
111 }
112 } else if (quant == Op.ANY) {
113 while (!res && qcursor.next()) {
114 Row crow = qcursor.getRow();
115 res = compare(op, row, crow);
116 }
117 } else {
118 throw new SQLException ("bad quantifier: " + quant, "42000");
119 }
120 return new ValueBoolean(not ^ res);
121 } finally {
122 qcursor.close();
123 }
124 }
125
126 public void visitSubExpressions(ExpressionVisitor ev) {
127 ev.visit(e);
128 ev.visit(q);
129 }
130
131 public void readExternal(ObjectInput in)
132 throws IOException , ClassNotFoundException
133 {
134 e = (Expression)in.readObject();
135 op = in.read();
136 quant = in.read();
137 q = (Expression)in.readObject();
138 not = in.read() == 1;
139 }
140
141 public void writeExternal(ObjectOutput out) throws IOException {
142 out.writeObject(e);
143 out.write(op);
144 out.write(quant);
145 out.writeObject(q);
146 out.write(not ? 1 : 0);
147 }
148
149 public String toString() {
150 StringBuffer sb = new StringBuffer (e.toString());
151 sb.append(' ');
152 sb.append(Op.toString(op));
153 sb.append(' ');
154 sb.append(Op.toString(quant));
155 sb.append(' ');
156 sb.append(q.toString());
157 return sb.toString();
158 }
159 }
160 |
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