/*
 * 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.flink.api.java.hadoop.common;

import org.apache.flink.annotation.Internal;
import org.apache.flink.api.common.io.RichInputFormat;
import org.apache.flink.core.io.InputSplit;

import org.apache.hadoop.security.Credentials;
import org.apache.hadoop.security.UserGroupInformation;

import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.lang.reflect.InvocationTargetException;
import java.lang.reflect.Method;

/** A common base for both "mapred" and "mapreduce" Hadoop input formats. */
@Internal
public abstract class HadoopInputFormatCommonBase<T, SPITTYPE extends InputSplit>
        extends RichInputFormat<T, SPITTYPE> {
    protected transient Credentials credentials;

    protected HadoopInputFormatCommonBase(Credentials creds) {
        this.credentials = creds;
    }

    protected void write(ObjectOutputStream out) throws IOException {
        this.credentials.write(out);
    }

    public void read(ObjectInputStream in) throws IOException {
        this.credentials = new Credentials();
        credentials.readFields(in);
    }

    /**
     * This method only exists because there is no UserGroupInformation.getCredentials() method in
     * Hadoop 1.x
     *
     * <p>Note that this method returns "null" in Hadoop 1.x environments.
     *
     * @param ugi The user information
     * @return new credentials object from the user information. MAY RETURN NULL!
     */
    public static Credentials getCredentialsFromUGI(UserGroupInformation ugi) {
        Method getCredentialsMethod = null;
        for (Method m : ugi.getClass().getMethods()) {
            if (m.getName().equals("getCredentials")) {
                getCredentialsMethod = m;
                break;
            }
        }
        if (getCredentialsMethod == null) {
            return null;
        } else {
            try {
                return (Credentials) getCredentialsMethod.invoke(ugi);
            } catch (InvocationTargetException | IllegalAccessException e) {
                throw new RuntimeException(
                        "Unable to get credentials from UserGroupInformation. This is only supported by Hadoop 2.2.0+");
            }
        }
    }
}

@@ -1199,93 +1199,8 @@
 eam;
-%0Aimport java.lang.reflect.InvocationTargetException;%0Aimport java.lang.reflect.Method;
 %0A%0A/*
@@ -1846,214 +1846,8 @@
 /**%0A
-     * This method only exists because there is no UserGroupInformation.getCredentials() method in%0A     * Hadoop 1.x%0A     *%0A     * %3Cp%3ENote that this method returns %22null%22 in Hadoop 1.x environments.%0A     *%0A
     
@@ -1949,25 +1949,8 @@
 ion.
- MAY RETURN NULL!
 %0A   
@@ -2046,684 +2046,36 @@
     
-Method getCredentialsMethod = null;%0A        for (Method m : ugi.getClass().getMethods()) %7B%0A            if (m.getName().equals(%22getCredentials%22)) %7B%0A                getCredentialsMethod = m;%0A                break;%0A            %7D%0A        %7D%0A        if (getCredentialsMethod == null) %7B%0A            return null;%0A        %7D else %7B%0A            try %7B%0A                return (Credentials) getCredentialsMethod.invoke(ugi);%0A            %7D catch (InvocationTargetException %7C IllegalAccessException e) %7B%0A                throw new RuntimeException(%0A                        %22Unable to get credentials from UserGroupInformation. This is only supported by Hadoop 2.2.0+%22);%0A            %7D%0A        %7D
+return ugi.getCredentials();
 %0A   

Remove support for Hadoop1.x in HadoopInputFormatCommonBase.getCredentialsFromUGI