org.apache.pulsar.sql.presto.PulsarConnectorUtils.java Source code

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Here is the source code for org.apache.pulsar.sql.presto.PulsarConnectorUtils.java

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/**
 * 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.pulsar.sql.presto;

import org.apache.avro.Schema;
import org.apache.commons.lang3.exception.ExceptionUtils;
import org.apache.pulsar.client.admin.PulsarAdmin;
import org.apache.pulsar.client.admin.PulsarAdminException;
import org.apache.pulsar.common.naming.TopicName;

import java.lang.reflect.Constructor;
import java.lang.reflect.InvocationTargetException;

public class PulsarConnectorUtils {

    public static Schema parseSchema(String schemaJson) {
        Schema.Parser parser = new Schema.Parser();
        return parser.parse(schemaJson);
    }

    public static boolean isPartitionedTopic(TopicName topicName, PulsarAdmin pulsarAdmin)
            throws PulsarAdminException {
        return pulsarAdmin.topics().getPartitionedTopicMetadata(topicName.toString()).partitions > 0;
    }

    /**
     * Create an instance of <code>userClassName</code> using provided <code>classLoader</code>.
     * This instance should implement the provided interface <code>xface</code>.
     *
     * @param userClassName user class name
     * @param xface the interface that the reflected instance should implement
     * @param classLoader class loader to load the class.
     * @return the instance
     */
    public static <T> T createInstance(String userClassName, Class<T> xface, ClassLoader classLoader) {
        Class<?> theCls;
        try {
            theCls = Class.forName(userClassName, true, classLoader);
        } catch (ClassNotFoundException cnfe) {
            throw new RuntimeException("User class must be in class path", cnfe);
        }
        if (!xface.isAssignableFrom(theCls)) {
            throw new RuntimeException(userClassName + " not " + xface.getName());
        }
        Class<T> tCls = (Class<T>) theCls.asSubclass(xface);
        try {
            Constructor<T> meth = tCls.getDeclaredConstructor();
            return meth.newInstance();
        } catch (InstantiationException ie) {
            throw new RuntimeException("User class must be concrete", ie);
        } catch (NoSuchMethodException e) {
            throw new RuntimeException("User class must have a no-arg constructor", e);
        } catch (IllegalAccessException e) {
            throw new RuntimeException("User class must a public constructor", e);
        } catch (InvocationTargetException e) {
            throw new RuntimeException("User class constructor throws exception", e);
        }
    }
}