org.apache.hadoop.hive.ql.udf.generic.GenericUDFToIntervalYearMonth Maven / Gradle / Ivy
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* to you under the Apache License, Version 2.0 (the
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*
* http://www.apache.org/licenses/LICENSE-2.0
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package org.apache.hadoop.hive.ql.udf.generic;
import org.apache.hadoop.hive.ql.exec.Description;
import org.apache.hadoop.hive.ql.exec.UDFArgumentException;
import org.apache.hadoop.hive.ql.exec.UDFArgumentLengthException;
import org.apache.hadoop.hive.ql.exec.vector.VectorizedExpressions;
import org.apache.hadoop.hive.ql.exec.vector.expressions.CastStringToIntervalYearMonth;
import org.apache.hadoop.hive.ql.metadata.HiveException;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.PrimitiveObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorConverter.HiveIntervalYearMonthConverter;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
/**
*
* GenericUDFIntervalYearMonth
*
* Example usage:
* ... CAST(<Interval string> as INTERVAL YEAR TO MONTH) ...
*
* Creates a HiveIntervalYearMonthWritable object using PrimitiveObjectInspectorConverter
*
*/
@Description(name = "interval_year_month",
value = "CAST( AS INTERVAL YEAR TO MONTH) - Returns the year-month interval represented by the string")
@VectorizedExpressions({CastStringToIntervalYearMonth.class})
public class GenericUDFToIntervalYearMonth extends GenericUDF {
private transient PrimitiveObjectInspector argumentOI;
private transient HiveIntervalYearMonthConverter tc;
@Override
public ObjectInspector initialize(ObjectInspector[] arguments) throws UDFArgumentException {
if (arguments.length < 1) {
throw new UDFArgumentLengthException(
"The function INTERVAL_YEAR_MONTH requires at least one argument, got "
+ arguments.length);
}
try {
argumentOI = (PrimitiveObjectInspector) arguments[0];
} catch (ClassCastException e) {
throw new UDFArgumentException(
"The function INTERVAL_YEAR_MONTH takes only primitive types");
}
tc = new HiveIntervalYearMonthConverter(argumentOI,
PrimitiveObjectInspectorFactory.writableHiveIntervalYearMonthObjectInspector);
return PrimitiveObjectInspectorFactory.writableHiveIntervalYearMonthObjectInspector;
}
@Override
public Object evaluate(DeferredObject[] arguments) throws HiveException {
Object o0 = arguments[0].get();
if (o0 == null) {
return null;
}
return tc.convert(o0);
}
@Override
public String getDisplayString(String[] children) {
assert (children.length == 1);
StringBuilder sb = new StringBuilder();
sb.append("CAST( ");
sb.append(children[0]);
sb.append(" AS INTERVAL YEAR TO MONTH)");
return sb.toString();
}
}