com.cloudera.sqoop.orm.TableClassName.java Source code

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Here is the source code for com.cloudera.sqoop.orm.TableClassName.java

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/**
 * Licensed to Cloudera, Inc. under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  Cloudera, Inc. 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 com.cloudera.sqoop.orm;

import com.cloudera.sqoop.SqoopOptions;

import org.apache.commons.logging.Log;
import org.apache.commons.logging.LogFactory;

/**
 * Reconciles the table name being imported with the class naming information
 * specified in SqoopOptions to determine the actual package and class name to
 * use for a table.
 */
public class TableClassName {

    public static final Log LOG = LogFactory.getLog(TableClassName.class.getName());

    private final SqoopOptions options;

    public TableClassName(final SqoopOptions opts) {
        if (null == opts) {
            throw new NullPointerException("Cannot instantiate a TableClassName on null options.");
        } else {
            this.options = opts;
        }
    }

    /**
     * Taking into account --class-name and --package-name, return the actual
     * package-part which will be used for a class. The actual table name being
     * generated-for is irrelevant; so not an argument.
     *
     * @return the package where generated ORM classes go. Will be null for
     * top-level.
     */
    public String getPackageForTable() {
        String predefinedClass = options.getClassName();
        if (null != predefinedClass) {
            // If the predefined classname contains a package-part, return that.
            int lastDot = predefinedClass.lastIndexOf('.');
            if (-1 == lastDot) {
                // No package part.
                return null;
            } else {
                // Return the string up to but not including the last dot.
                return predefinedClass.substring(0, lastDot);
            }
        } else {
            // If the user has specified a package name, return it.
            // This will be null if the user hasn't specified one -- as we expect.
            return options.getPackageName();
        }
    }

    /**
     * @param tableName the name of the table being imported.
     * @return the full name of the class to generate/use to import a table.
     */
    public String getClassForTable(String tableName) {
        String predefinedClass = options.getClassName();
        if (predefinedClass != null) {
            // The user's chosen a specific class name for this job.
            return predefinedClass;
        }

        String queryName = tableName;
        if (null == queryName) {
            queryName = "QueryResult";
        }

        String packageName = options.getPackageName();
        if (null != packageName) {
            // return packageName.queryName.
            return packageName + "." + queryName;
        }

        // no specific class; no specific package.
        // Just make sure it's a legal identifier.
        return ClassWriter.toIdentifier(queryName);
    }

    /**
     * @return just the last segment of the class name -- all package info
     * stripped. 
     */
    public String getShortClassForTable(String tableName) {
        String fullClass = getClassForTable(tableName);
        if (null == fullClass) {
            return null;
        }

        int lastDot = fullClass.lastIndexOf('.');
        if (-1 == lastDot) {
            return fullClass;
        } else {
            return fullClass.substring(lastDot + 1, fullClass.length());
        }
    }
}