编写Java代码，实现hive UDTF函数，函数需要传入两个String类型参数

好的，下面是一个简单的Java代码，实现了一个hive UDTF函数，函数名为`my_udtf`，需要传入两个String类型参数`str1`和`str2`：

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.UDFType;
import org.apache.hadoop.hive.ql.udf.generic.GenericUDTF;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.ObjectInspectorFactory;
import org.apache.hadoop.hive.serde2.objectinspector.StructObjectInspector;
import org.apache.hadoop.hive.serde2.objectinspector.primitive.PrimitiveObjectInspector;
import org.apache.hadoop.io.Text;

import java.util.ArrayList;

@Description(name = "my_udtf", value = "_FUNC_(str1, str2) - returns two strings as columns")
@UDFType(deterministic = true, stateful = false)
public class MyUDTF extends GenericUDTF {

    private PrimitiveObjectInspector stringOI = null;

    @Override
    public StructObjectInspector initialize(ObjectInspector[] args) throws UDFArgumentException {
        if (args.length != 2) {
            throw new UDFArgumentLengthException("my_udtf only takes two arguments");
        }

        if (args[0].getCategory() != ObjectInspector.Category.PRIMITIVE
                || ((PrimitiveObjectInspector) args[0]).getPrimitiveCategory() != PrimitiveObjectInspector.PrimitiveCategory.STRING) {
            throw new UDFArgumentException("my_udtf first argument must be a string");
        }

        if (args[1].getCategory() != ObjectInspector.Category.PRIMITIVE
                || ((PrimitiveObjectInspector) args[1]).getPrimitiveCategory() != PrimitiveObjectInspector.PrimitiveCategory.STRING) {
            throw new UDFArgumentException("my_udtf second argument must be a string");
        }

        stringOI = (PrimitiveObjectInspector) args[0];

        ArrayList<String> fieldNames = new ArrayList<String>();
        ArrayList<ObjectInspector> fieldOIs = new ArrayList<ObjectInspector>();
        fieldNames.add("col1");
        fieldNames.add("col2");
        fieldOIs.add(PrimitiveObjectInspectorFactory.writableStringObjectInspector);
        fieldOIs.add(PrimitiveObjectInspectorFactory.writableStringObjectInspector);

        return ObjectInspectorFactory.getStandardStructObjectInspector(fieldNames, fieldOIs);
    }

    @Override
    public void process(Object[] record) throws UDFArgumentException {
        String str1 = (String) stringOI.getPrimitiveJavaObject(record[0]);
        String str2 = (String) stringOI.getPrimitiveJavaObject(record[1]);
        forward(new Text(str1), new Text(str2));
    }

    @Override
    public void close() throws UDFArgumentException {
    }
}

这个函数会返回一个包含两个字符串列的结果集，可以在hive中使用类似以下的语句调用：

SELECT my_udtf('hello', 'world') FROM my_table;

其中`my_table`是你的hive表名。