package org.jinq.jpa.jpqlquery;
import scala.Tuple2;
import scala.Tuple3;
import scala.Tuple4;
import scala.Tuple5;
import scala.Tuple8;
public class ScalaTupleRowReader<T> implements RowReader<T>
{
public static final String TUPLE2_CLASS = Tuple2.class.getTypeName().replace('.', '/');
public static final String TUPLE3_CLASS = Tuple3.class.getTypeName().replace('.', '/');
public static final String TUPLE4_CLASS = Tuple4.class.getTypeName().replace('.', '/');
public static final String TUPLE5_CLASS = Tuple5.class.getTypeName().replace('.', '/');
public static final String TUPLE8_CLASS = Tuple8.class.getTypeName().replace('.', '/');
RowReader<?>[] subreaders;
ScalaTupleRowReader(RowReader<?>[] subreaders)
{
this.subreaders = subreaders;
}
@Override public int getNumColumns()
{
int sum = 0;
for (int n = 0; n < subreaders.length; n++)
sum += subreaders[n].getNumColumns();
return sum;
}
@Override
public T readResult(Object result)
{
if (!(result instanceof Object[]))
throw new IllegalArgumentException("Expecting an array of results");
return readResult((Object[])result, 0);
}
@Override
public T readResult(Object[] results, int start)
{
Object [] data = new Object[subreaders.length];
int offset = 0;
for (int n = 0; n < subreaders.length; n++)
{
data[n] = subreaders[n].readResult(results, start + offset);
offset += subreaders[n].getNumColumns();
}
return createTuple(data);
}
public int getColumnForIndex(int index)
{
if (index < 0 || index >= subreaders.length) return -1;
int offset = 0;
for (int n = 0; n < index; n++)
offset += subreaders[n].getNumColumns();
return offset;
}
public RowReader<?> getReaderForIndex(int index)
{
if (index < 0 || index >= subreaders.length) return null;
return subreaders[index];
}
private T createTuple(Object[] data)
{
switch(subreaders.length)
{
case 2:
return (T)new Tuple2(data[0], data[1]);
case 3:
return (T)new Tuple3(data[0], data[1], data[2]);
case 4:
return (T)new Tuple4(data[0], data[1], data[2], data[3]);
case 5:
return (T)new Tuple5(data[0], data[1], data[2], data[3], data[4]);
case 8:
return (T)new Tuple8(data[0], data[1], data[2], data[3], data[4], data[5], data[6], data[7]);
default:
throw new IllegalArgumentException("Creating a tuple with a SQLReader with unknown size " + subreaders.length);
}
}
public static <T> ScalaTupleRowReader<T> createReaderForTuple(RowReader<?>...subreaders)
{
return new ScalaTupleRowReader<T>(subreaders);
}
public static <T> ScalaTupleRowReader<T> createReaderForTuple(String tupleInternalName, RowReader<?>...subreaders)
{
if (TUPLE2_CLASS.equals(tupleInternalName)) {
if (subreaders.length != 2)
throw new IllegalArgumentException("Wrong number of arguments when creating tuple");
}
else if (TUPLE3_CLASS.equals(tupleInternalName))
{
if (subreaders.length != 3)
throw new IllegalArgumentException("Wrong number of arguments when creating tuple");
}
else if (TUPLE4_CLASS.equals(tupleInternalName))
{
if (subreaders.length != 4)
throw new IllegalArgumentException("Wrong number of arguments when creating tuple");
}
else if (TUPLE5_CLASS.equals(tupleInternalName))
{
if (subreaders.length != 5)
throw new IllegalArgumentException("Wrong number of arguments when creating tuple");
}
else if (TUPLE8_CLASS.equals(tupleInternalName))
{
if (subreaders.length != 8)
throw new IllegalArgumentException("Wrong number of arguments when creating tuple");
}
else
throw new IllegalArgumentException("Creating a tuple with a SQLReader with unknown size " + subreaders.length);
return new ScalaTupleRowReader<T>(subreaders);
}
}