blob: 437d5549c971c5a7fac8b1adcc32f8242a9e1475 (
plain) (
blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
|
// Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
package com.yahoo.vespa.indexinglanguage;
import com.yahoo.vespa.indexinglanguage.expressions.Expression;
import com.yahoo.vespa.indexinglanguage.expressions.StatementExpression;
/**
* Inserts a "newTransform()" before expressions that "requiresTransform()"
*
* @author Simon Thoresen Hult
*/
public abstract class ValueTransformProvider extends ExpressionConverter {
private final Class<? extends Expression> transformClass;
private boolean transformed = false;
private boolean duplicate = false;
public ValueTransformProvider(Class<? extends Expression> transformClass) {
this.transformClass = transformClass;
}
@Override
public final ExpressionConverter branch() {
return clone();
}
@Override
protected final boolean shouldConvert(Expression exp) {
if (transformClass.isInstance(exp)) {
if (transformed) {
duplicate = true;
return true;
}
transformed = true;
return false;
}
if (exp.createdOutputType() != null) {
transformed = false;
return false;
}
if ( ! requiresTransform(exp)) {
return false;
}
if (transformed) {
return false;
}
return true;
}
@Override
protected final Expression doConvert(Expression exp) {
if (duplicate) {
duplicate = false;
return null;
}
transformed = true;
return new StatementExpression(newTransform(), exp);
}
protected abstract boolean requiresTransform(Expression exp);
protected abstract Expression newTransform();
}
|
