JDBCExternalTableDescription.java

/*******************************************************************************
 * Copyright (c) 1998, 2015 Oracle and/or its affiliates. All rights reserved.
 * This program and the accompanying materials are made available under the
 * terms of the Eclipse Public License v1.0 and Eclipse Distribution License v. 1.0
 * which accompanies this distribution.
 * The Eclipse Public License is available at http://www.eclipse.org/legal/epl-v10.html
 * and the Eclipse Distribution License is available at
 * http://www.eclipse.org/org/documents/edl-v10.php.
 *
 * Contributors:
 *     Oracle - initial API and implementation from Oracle TopLink
******************************************************************************/
package org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.jdbc;

import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.sql.SQLException;

import org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTable;
import org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription;
import org.eclipse.persistence.tools.workbench.utility.NameTools;
import org.eclipse.persistence.tools.workbench.utility.string.StringTools;


/**
 *
 */
final class JDBCExternalTableDescription implements ExternalTableDescription {
    private final JDBCExternalDatabase database;
    private final String catalogName;
    private final String schemaName;
    private final String name;
    private final String qualifiedName;    // cache the qualified name, since it will not change
    private ExternalTable externalTable;        // pseudo-final


    // ********** constructor/initialization **********

    /**
     * Construct an external table description from the current row
     * in the specified result set. The result set corresponds to the
     * result set returned from DatabaseMetaData#getTables(String, String, String, String[]).
     * @see java.sql.DatabaseMetaData#getTables(String, String, String, String[])
     */
    JDBCExternalTableDescription(ResultSet resultSet, JDBCExternalDatabase database) throws SQLException {
        this(
            // trim all the strings - some databases return fixed-length strings;
            // these calls *shouldn't* throw any SQL exceptions...
            trim(resultSet.getString(1)),        // TABLE_CAT
            trim(resultSet.getString(2)),        // TABLE_SCHEM
            trim(resultSet.getString(3)),        // TABLE_NAME
            database
        );
    }

    JDBCExternalTableDescription(String catalogName, String schemaName, String name, JDBCExternalDatabase database) {
        super();
        this.catalogName = catalogName;
        this.schemaName = schemaName;
        this.name = name;
        this.qualifiedName = this.buildQualifiedName();
        this.database = database;
    }

    /**
     * trim down the specified string, to null if necessary
     */
    private static String trim(String s) {
        if (s == null) {
            return null;
        }
        s = s.trim();
        return (s.length() == 0) ? null : s;
    }

    private String buildQualifiedName() {
        return NameTools.buildQualifiedDatabaseObjectName(this.catalogName, this.schemaName, this.name);
    }


    // ********** ExternalTableDescription implementation **********

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription#getCatalogName()
     */
    public String getCatalogName() {
        return this.catalogName;
    }

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription#getSchemaName()
     */
    public String getSchemaName() {
        return this.schemaName;
    }

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription#getName()
     */
    public String getName() {
        return this.name;
    }

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription#getQualifiedName()
     */
    public String getQualifiedName() {
        return this.qualifiedName;
    }

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.ExternalTableDescription#getTable()
     */
    public ExternalTable getTable() {
        if (this.externalTable == null) {
            this.externalTable = this.buildExternalTable();
        }
        return this.externalTable;
    }

    /**
     * @see org.eclipse.persistence.tools.workbench.mappingsmodel.spi.db.TableDescription#getAdditionalInfo()
     */
    public String getAdditionalInfo() {
        try {
            return this.metaData().getURL();
        } catch (SQLException ex) {
            return null;
        }
    }


    // ********** behavior **********

    private ExternalTable buildExternalTable() {
        try {
            return new JDBCExternalTable(this);
        } catch (SQLException ex) {
            throw new RuntimeException(ex);
        }
    }


    // ********** queries **********

    DatabaseMetaData metaData() {
        return this.database.metaData();
    }

    JDBCExternalDatabase getDatabase() {
        return this.database;
    }

    public String toString() {
        return StringTools.buildToStringFor(this, this.qualifiedName);
    }

}