AggFinder (Apache Calcite API)

java.lang.Object
- org.apache.calcite.sql.util.SqlBasicVisitor<java.lang.Void>
- - org.apache.calcite.sql.validate.AggVisitor
  - - org.apache.calcite.sql.validate.AggFinder

All Implemented Interfaces:

SqlVisitor<java.lang.Void>
```
class AggFinder
extends AggVisitor
```
Visitor that looks for an aggregate function inside a tree of SqlNode objects and throws Util.FoundOne when it finds one.

Nested Class Summary

Nested Classes
Modifier and Type Class Description

(package private) static class AggFinder.AggIterable
Iterates over all aggregates.
- Nested classes/interfaces inherited from class org.apache.calcite.sql.util.SqlBasicVisitor
  SqlBasicVisitor.ArgHandler<R>, SqlBasicVisitor.ArgHandlerImpl<R>

Field Summary
- Fields inherited from class org.apache.calcite.sql.validate.AggVisitor
  aggregate, delegate, group, opTab, over

Constructor Summary

Constructors
Constructor	Description
`AggFinder(SqlOperatorTable opTab, boolean over, boolean aggregate, boolean group, AggFinder delegate)`	Creates an AggFinder.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`SqlCall`	`findAgg(java.util.List<SqlNode> nodes)`
`SqlCall`	`findAgg(SqlNode node)`	Finds an aggregate.
`(package private) java.lang.Iterable<SqlCall>`	`findAll(java.lang.Iterable<SqlNode> nodes)`	Creates a copy of this finder that has the same parameters as this, then returns the list of all aggregates found.
`protected java.lang.Void`	`found(SqlCall call)`

Methods inherited from class org.apache.calcite.sql.validate.AggVisitor
visit

Methods inherited from class org.apache.calcite.sql.util.SqlBasicVisitor
visit, visit, visit, visit, visit, visit

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

- Constructor Detail
  - AggFinder
```
AggFinder(SqlOperatorTable opTab,
          boolean over,
          boolean aggregate,
          boolean group,
          AggFinder delegate)
```
    Creates an AggFinder.
    
    Parameters:
    
    opTab - Operator table
    
    over - Whether to find windowed function calls agg(x) OVER windowSpec
    
    aggregate - Whether to find non-windowed aggregate calls
    
    group - Whether to find group functions (e.g. TUMBLE)
    
    delegate - Finder to which to delegate when processing the arguments
- Method Detail
  - findAgg
```
public SqlCall findAgg(SqlNode node)
```
    Finds an aggregate.
    
    Parameters:
    
    node - Parse tree to search
    
    Returns:
    
    First aggregate function in parse tree, or null if not found
  - findAgg
```
public SqlCall findAgg(java.util.List<SqlNode> nodes)
```
  - found
```
protected java.lang.Void found(SqlCall call)
```
    Specified by:
    
    found in class AggVisitor
  - findAll
```
java.lang.Iterable<SqlCall> findAll(java.lang.Iterable<SqlNode> nodes)
```
    Creates a copy of this finder that has the same parameters as this, then returns the list of all aggregates found.