/**
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package org.apache.tajo.engine.function.string;
import org.apache.commons.codec.binary.Base64;
import org.apache.commons.lang.StringEscapeUtils;
import org.apache.tajo.catalog.Column;
import org.apache.tajo.common.TajoDataTypes;
import org.apache.tajo.datum.Datum;
import org.apache.tajo.datum.DatumFactory;
import org.apache.tajo.datum.NullDatum;
import org.apache.tajo.engine.function.GeneralFunction;
import org.apache.tajo.engine.function.annotation.Description;
import org.apache.tajo.engine.function.annotation.ParamTypes;
import org.apache.tajo.storage.Tuple;
/**
* Function definition
*
* bytearray decode(string text, format text)
*/
@Description(
functionName = "decode",
description = "Decode binary data from textual representation in string. "
+ "Options for format are same as in encode.",
detail = "format is one of 'base64', 'hex'",
example = "> SELECT decode('MTIzAAE=', 'base64');\n"
+ "\\x3132330001",
returnType = TajoDataTypes.Type.TEXT,
paramTypes = {@ParamTypes(paramTypes = {TajoDataTypes.Type.TEXT, TajoDataTypes.Type.TEXT})}
)
public class Decode extends GeneralFunction {
public Decode() {
super(new Column[] {
new Column("string", TajoDataTypes.Type.TEXT),
new Column("format", TajoDataTypes.Type.TEXT)
});
}
@Override
public Datum eval(Tuple params) {
Datum datum = params.get(0);
Datum formatType = params.get(1);
String decodedBase64Text="";
String decodedHexString="";
if(datum instanceof NullDatum) return NullDatum.get();
if(formatType instanceof NullDatum) return NullDatum.get();
if(formatType.asChars().toLowerCase().equals("base64")) {
try {
// Base64
decodedBase64Text = new String(Base64.decodeBase64(datum.asChars().getBytes()));
}
catch (Exception e) {
return NullDatum.get();
}
return DatumFactory.createText(StringEscapeUtils.escapeJava(decodedBase64Text));
}
else if(formatType.asChars().toLowerCase().equals("hex")) {
try {
// Hex
decodedHexString = HexStringConverter.getInstance().decodeHex(datum.asChars());
}
catch (Exception e) {
return NullDatum.get();
}
return DatumFactory.createText(StringEscapeUtils.escapeJava(decodedHexString));
}
else
return NullDatum.get();
}
}