com.google.visualization.datasource.query
Class QueryFilter

java.lang.Object
  com.google.visualization.datasource.query.QueryFilter

Direct Known Subclasses:

ColumnIsNullFilter, ComparisonFilter, CompoundFilter, NegationFilter

public abstract class QueryFilter
extends java.lang.Object

A query filter. Any class that implements this interface can act as a filter, i.e., be the part of a query that decides for a given TableRow if that row is part of the result set.

Author:

Yonatan B.Y.

Constructor Summary

QueryFilter()

Method Summary

protected abstract java.util.List<AggregationColumn>	getAggregationColumns() Returns a list of all aggregation columns this filter uses.
abstract java.util.Set<java.lang.String>	getAllColumnIds() Returns all the columnIds this filter uses.
abstract java.util.List<ScalarFunctionColumn>	getScalarFunctionColumns() Returns a list of all scalarFunctionColumns this filter uses.
abstract boolean	isMatch(DataTable table, TableRow row) Checks if this row should be part of the result set.
abstract java.lang.String	toQueryString() Returns a string that, when parsed by the query parser, should return an identical filter.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

QueryFilter

public QueryFilter()

Method Detail

isMatch

public abstract boolean isMatch(DataTable table,
                                TableRow row)

Checks if this row should be part of the result set.

Parameters:

table - The table containing this row.

row - The row to check.

Returns:

true if this row should be part of the result set, false otherwise.

getAllColumnIds

public abstract java.util.Set<java.lang.String> getAllColumnIds()

Returns all the columnIds this filter uses.

Returns:

All the columnIds this filter uses.

getScalarFunctionColumns

public abstract java.util.List<ScalarFunctionColumn> getScalarFunctionColumns()

Returns a list of all scalarFunctionColumns this filter uses.

Returns:

A list of all scalarFunctionColumns this filter uses.

getAggregationColumns

protected abstract java.util.List<AggregationColumn> getAggregationColumns()

Returns a list of all aggregation columns this filter uses. This is kept for future use, as currently filters are not allowed to have aggregation columns. This is still used currently for validation purposes.

Returns:

A list of all aggregation columns this filter uses.

toQueryString

public abstract java.lang.String toQueryString()

Returns a string that, when parsed by the query parser, should return an identical filter. The string returned does not contain the WHERE keyword.

Returns:

A string form of this filter.