axiondatabasemetadata.java

开源的axion的数据库代码

/*
 * $Id: AxionDatabaseMetaData.java,v 1.17 2003/07/10 22:53:50 rwald Exp $
 * =======================================================================
 * Copyright (c) 2002-2003 Axion Development Team.  All rights reserved.
 *  
 * Redistribution and use in source and binary forms, with or without 
 * modification, are permitted provided that the following conditions 
 * are met:
 * 
 * 1. Redistributions of source code must retain the above 
 *    copyright notice, this list of conditions and the following 
 *    disclaimer. 
 *   
 * 2. Redistributions in binary form must reproduce the above copyright 
 *    notice, this list of conditions and the following disclaimer in 
 *    the documentation and/or other materials provided with the 
 *    distribution. 
 *   
 * 3. The names "Tigris", "Axion", nor the names of its contributors may 
 *    not be used to endorse or promote products derived from this 
 *    software without specific prior written permission. 
 *  
 * 4. Products derived from this software may not be called "Axion", nor 
 *    may "Tigris" or "Axion" appear in their names without specific prior
 *    written permission.
 *   
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A
 * PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * =======================================================================
 */

package org.axiondb.jdbc;

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

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

/**
 * A {@link DatabaseMetaData} implementation.
 * 
 * @TODO Support currently unsupported JDBC 3 methods.
 * @version $Revision: 1.17 $ $Date: 2003/07/10 22:53:50 $
 * @author Rodney Waldhoff
 */
public class AxionDatabaseMetaData implements DatabaseMetaData {

    public AxionDatabaseMetaData(AxionConnection conn, Database db) {
        _connection = conn;
        _db = db;
    }

    //-------------------------------------------------------------------------    

    /** Currently returns "<code>AxionDB</code>". */
    public String getDatabaseProductName() throws SQLException {
        return "AxionDB"; // XXX FIX ME XXX
    }

    /** Currently returns "<code>1.0M1</code>". */
    public String getDatabaseProductVersion() throws SQLException {
        return AXION_VERSION;
    }

    /** Currently returns "<code>Axion JDBC Driver". */
    public String getDriverName() throws SQLException {
        return "Axion JDBC Driver";
    }

    /** Currently returns "<code>1.0M1</code>". */
    public String getDriverVersion() throws SQLException {
        return AXION_VERSION;
    }

    /** Currently returns <code>0</code>. */
    public int getDriverMajorVersion() {
        return DB_MAJOR_VERSION;
    }

    /** Currently returns <code>1</code>. */
    public int getDriverMinorVersion() {
        return DB_MINOR_VERSION;
    }

    //-------------------------------------------------------------------------    

    /** Currently returns <code>null</code>. */
    public String getUserName() throws SQLException {  
        return null;
    }

    /** Currently returns <code>false</code>. */
    public boolean allProceduresAreCallable() throws SQLException {
        return false;
    }

    /** Returns <code>true</code>, since all tables are indeed selectable. */
    public boolean allTablesAreSelectable() throws SQLException {
        return true;
    }

    /** 
     * Returns <code>true</code> when this database is 
     * known to be read only, false otherwise.
     */
    public boolean isReadOnly() throws SQLException {
        return _db.isReadOnly();
    }

    /** Returns <code>false</code>, since Axion currently ignores case in identifiers. */
    public boolean supportsMixedCaseIdentifiers() throws SQLException {
        return false;
    }

    /** Returns <code>true</code>, since Axion supports column aliasing. */
    public boolean supportsColumnAliasing() throws SQLException {
        return true;
    }
    
    /** Returns <code>true</code>, since Axion supports addBatch,clearBatch and executeBatch. */
    public boolean supportsBatchUpdates() throws SQLException {
        return true;
    }

    /** Returns my {@link Connection}. */
    public Connection getConnection() throws SQLException {
        return _connection;
    }

    /** 
     * Returns <code>true</code>, since <code>null</code>s are
     * considered greater than any non-<code>null</code> value.
     */
    public boolean nullsAreSortedHigh() throws SQLException {
        return true;
    }

    /** 
     * Returns <code>false</code>, since <code>null</code>s are
     * considered greater than any non-<code>null</code> value.
     * @see #nullsAreSortedHigh
     */
    public boolean nullsAreSortedLow() throws SQLException {
        return false;
    }
    
    /** 
     * Returns <code>false</code>, since <code>null</code>s are
     * considered greater than any non-<code>null</code> value.
     * @see #nullsAreSortedHigh
     */
    public boolean nullsAreSortedAtStart() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>false</code>, since <code>null</code>s are
     * considered greater than any non-<code>null</code> value.
     * @see #nullsAreSortedHigh
     */
    public boolean nullsAreSortedAtEnd() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>false</code>, since Axion currently
     * ignores case in identifiers, and stores them internally 
     * as upper case values.
     */
    public boolean storesLowerCaseIdentifiers() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>false</code>, since Axion currently
     * ignores case in identifiers.
     */
    public boolean supportsMixedCaseQuotedIdentifiers() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>false</code>, since Axion currently
     * ignores case in identifiers, and stores them internally 
     * as upper case values.
     */
    public boolean storesMixedCaseQuotedIdentifiers() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>true</code>, since Axion currently
     * ignores case in identifiers, and stores them internally 
     * as upper case values.
     */
    public boolean storesUpperCaseIdentifiers() throws SQLException {
        return true;
    }

    /** 
     * Returns <code>false</code>, since Axion currently
     * ignores case in identifiers, and stores them internally 
     * as upper case values.  Quoted identifiers are also
     * currently unsupported.
     */
    public boolean storesLowerCaseQuotedIdentifiers() throws SQLException {
        return false;
    }


    /** 
     * Returns <code>false</code>, since Axion currently
     * ignores case in identifiers, and stores them internally 
     * as upper case values.
     */
    public boolean storesMixedCaseIdentifiers() throws SQLException {
        return false;
    }

    /** 
     * Returns <code>0</code>, since Axion has no hard limit
     * on the size of a row.
     */
    public int getMaxRowSize() throws SQLException {
        return 0;
    }

    /** 
     * Returns <code>0</code>, since Axion has no hard limit
     * on the size of a statement.
     */
    public int getMaxStatementLength() throws SQLException {
        return 0;
    }

    /** 
     * Returns <code>0</code>, since Axion has no hard limit
     * on the number of connections.
     */
    public int getMaxConnections() throws SQLException {
        return 0;
    }

    /** 
     * Returns <code>0</code>, since Axion has no hard limit
     * on the length of a column name.
     */
    public int getMaxColumnNameLength() throws SQLException {
        return Integer.MAX_VALUE;
    }

    /** 
     * Returns <code>1</code>, since Axion currently doesn't
     * support multi-column indices.
     */
    public int getMaxColumnsInIndex() throws SQLException {
        return 1; // 0 when we support multi-column indices
    }

    /** 
     * Returns {@link java.lang.Integer#MAX_VALUE}, the
     * maximum number of tables Axion can manage in a single
     * SELECT statement.
     */
    public int getMaxTablesInSelect() throws SQLException {
        return Integer.MAX_VALUE;
    }

    /** 
     * Returns {@link java.lang.Integer#MAX_VALUE}, the
     * maximum number of columns Axion can manage in a single
     * ORDER BY clause.
     */
    public int getMaxColumnsInOrderBy() throws SQLException {
        return Integer.MAX_VALUE;
    }

    /** 
     * Returns {@link java.lang.Integer#MAX_VALUE}, the
     * maximum number of columns Axion can manage in a single
     * SELECT clause.
     */
    public int getMaxColumnsInSelect() throws SQLException {
        return Integer.MAX_VALUE;
    }
    
    /** 
     * Returns {@link java.lang.Integer#MAX_VALUE}, the
     * maximum number of columns Axion can manage in a single
     * table.
     */
    public int getMaxColumnsInTable() throws SQLException {
        return Integer.MAX_VALUE;
    }

    /** 
     * Returns 0.
     */
    public int getMaxColumnsInGroupBy() throws SQLException {
        return 0;
    }

    /** 
     * Returns <code>false</code> since UNION queries are
     * currently not supported..
     */
    public boolean supportsUnion() throws SQLException {
        return false;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxSchemaNameLength() throws SQLException {
        return 0;
    }
            
    /** Returns <code>0</code>. */
    public int getMaxStatements() throws SQLException {
        return 0;
    }
    
    /** Returns <code>Integer.MAX_VALUE</code>. */
    public int getMaxTableNameLength() throws SQLException {
        return Integer.MAX_VALUE;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxUserNameLength() throws SQLException {
        return 0;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxBinaryLiteralLength() throws SQLException {
        return 0;
    }
        
    /** Returns <code>0</code>. */
    public int getMaxCharLiteralLength() throws SQLException {
        return 0;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxIndexLength() throws SQLException {
        return 0;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxProcedureNameLength() throws SQLException {
        return 0;
    }
    
    /** Returns <code>0</code>. */
    public int getMaxCatalogNameLength() throws SQLException {
        return 0;
    }
    
    /** Returns {@link Connection#TRANSACTION_SERIALIZABLE}. */
    public int getDefaultTransactionIsolation() throws SQLException {
        return Connection.TRANSACTION_SERIALIZABLE;
    }

    /** Returns the connect string used to establish my {@link Connection}. */
    public String getURL() throws SQLException {
        return _connection.getURL();
    }

    /** Returns <code>false</code> as this feature is currently not supported. */
    public boolean supportsSelectForUpdate() throws SQLException {
        return false;
    }