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1
5 package org.h2.expression;
6
7 import java.sql.SQLException  ;
8
9 import org.h2.command.Parser;
10 import org.h2.engine.FunctionAlias;
11 import org.h2.engine.Session;
12 import org.h2.table.ColumnResolver;
13 import org.h2.table.TableFilter;
14 import org.h2.value.Value;
15 import org.h2.value.ValueNull;
16 import org.h2.value.ValueResultSet;
17
18 public class JavaFunction extends Expression implements FunctionCall {
19
20 private FunctionAlias functionAlias;
21 private Expression[] args;
22
23 public JavaFunction(FunctionAlias functionAlias, Expression[] args) {
24 this.functionAlias = functionAlias;
25 this.args = args;
26 }
27
28 public Value getValue(Session session) throws SQLException {
29 return functionAlias.getValue(session, args);
30 }
31
32 public int getType() {
33 return functionAlias.getDataType();
34 }
35
36 public void mapColumns(ColumnResolver resolver, int level) throws SQLException {
37 for (int i = 0; i < args.length; i++) {
38 args[i].mapColumns(resolver, level);
39 }
40 }
41
42 public Expression optimize(Session session) throws SQLException {
43 for(int i=0; i<args.length; i++) {
44 Expression e = args[i].optimize(session);
45 args[i] = e;
46 }
47 return this;
48 }
49
50 public void setEvaluatable(TableFilter tableFilter, boolean b) {
51 for (int i = 0; i < args.length; i++) {
52 Expression e = args[i];
53 if (e != null) {
54 e.setEvaluatable(tableFilter, b);
55 }
56 }
57 }
58
59 public int getScale() {
60 return 0;
61 }
62
63 public long getPrecision() {
64 return 0;
65 }
66
67 public String getSQL() {
68 StringBuffer buff = new StringBuffer ();
69 buff.append(Parser.quoteIdentifier(functionAlias.getName()));
70 buff.append('(');
71 for (int i = 0; i < args.length; i++) {
72 if (i > 0) {
73 buff.append(", ");
74 }
75 Expression e = args[i];
76 buff.append(e.getSQL());
77 }
78 buff.append(')');
79 return buff.toString();
80 }
81
82 public void updateAggregate(Session session) throws SQLException {
83 for (int i = 0; i < args.length; i++) {
84 Expression e = args[i];
85 if (e != null) {
86 e.updateAggregate(session);
87 }
88 }
89 }
90
91 public FunctionAlias getFunctionAlias() {
92 return functionAlias;
93 }
94
95 public String getName() {
96 return functionAlias.getName();
97 }
98
99 public int getParameterCount() {
100 return functionAlias.getParameterCount();
101 }
102
103 public ValueResultSet getValueForColumnList(Session session, Expression[] args) throws SQLException {
104 Value v = functionAlias.getValue(session, args, true);
105 return v == ValueNull.INSTANCE ? null : (ValueResultSet) v;
106 }
107
108 public Expression[] getArgs() {
109 return args;
110 }
111
112 public boolean isEverything(ExpressionVisitor visitor) {
113 if(visitor.type == ExpressionVisitor.DETERMINISTIC) {
114 return false;
116 }
117 for (int i = 0; i < args.length; i++) {
118 Expression e = args[i];
119 if (e != null && !e.isEverything(visitor)) {
120 return false;
121 }
122 }
123 return true;
124 }
125
126 public int getCost() {
127 int cost = functionAlias.hasConnectionParam() ? 25 : 5;
128 for(int i=0; i<args.length; i++) {
129 cost += args[i].getCost();
130 }
131 return cost;
132 }
133
134 }
135 |
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