org.objectstyle.cayenne.dba.mysql.MySQLAdapter Maven / Gradle / Ivy
The newest version!
/* ====================================================================
*
* The ObjectStyle Group Software License, version 1.1
* ObjectStyle Group - http://objectstyle.org/
*
* Copyright (c) 2002-2005, Andrei (Andrus) Adamchik and individual authors
* of the software. 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 end-user documentation included with the redistribution, if any,
* must include the following acknowlegement:
* "This product includes software developed by independent contributors
* and hosted on ObjectStyle Group web site (http://objectstyle.org/)."
* Alternately, this acknowlegement may appear in the software itself,
* if and wherever such third-party acknowlegements normally appear.
*
* 4. The names "ObjectStyle Group" and "Cayenne" must not be used to endorse
* or promote products derived from this software without prior written
* permission. For written permission, email
* "andrus at objectstyle dot org".
*
* 5. Products derived from this software may not be called "ObjectStyle"
* or "Cayenne", nor may "ObjectStyle" or "Cayenne" appear in their
* names without prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED 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 OBJECTSTYLE GROUP OR
* ITS 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.
* ====================================================================
*
* This software consists of voluntary contributions made by many
* individuals and hosted on ObjectStyle Group web site. For more
* information on the ObjectStyle Group, please see
* Foreign Key Constraint Handling
*
* Foreign key constraints are supported by InnoDB engine and NOT supported by MyISAM
* engine. This adapter by default assumes MyISAM, so
* {@link org.objectstyle.cayenne.dba.JdbcAdapter#supportsFkConstraints()} will return
* false. Users can manually change this by calling
* setSupportsFkConstraints(true) or better by using an
* {@link org.objectstyle.cayenne.dba.AutoAdapter}, i.e. not entering the adapter name at
* all for the DataNode, letting Cayenne guess it in runtime. In the later case Cayenne
* will check the table_type MySQL variable to detect whether InnoDB is the
* default, and configure the adapter accordingly.
*
Sample Connection Settings
*
* - Adapter name: org.objectstyle.cayenne.dba.mysql.MySQLAdapter
* - DB URL: jdbc: mysql://serverhostname/dbname
* - Driver Class: com.mysql.jdbc.Driver
*
*
* @author Andrus Adamchik
*/
public class MySQLAdapter extends JdbcAdapter {
public MySQLAdapter() {
// init defaults
this.setSupportsFkConstraints(false);
this.setSupportsUniqueConstraints(true);
this.setSupportsGeneratedKeys(true);
}
/**
* Uses special action builder to create the right action.
*
* @since 1.2
*/
public SQLAction getAction(Query query, DataNode node) {
return query.createSQLAction(new MySQLActionBuilder(this, node
.getEntityResolver()));
}
public String dropTable(DbEntity entity) {
return "DROP TABLE IF EXISTS " + entity.getFullyQualifiedName() + " CASCADE";
}
/**
* Installs appropriate ExtendedTypes used as converters for passing values between
* JDBC and Java layers.
*/
protected void configureExtendedTypes(ExtendedTypeMap map) {
super.configureExtendedTypes(map);
// must handle CLOBs as strings, otherwise there
// are problems with NULL clobs that are treated
// as empty strings... somehow this doesn't happen
// for BLOBs (ConnectorJ v. 3.0.9)
map.registerType(new CharType(false, false));
map.registerType(new ByteArrayType(false, false));
}
public DbAttribute buildAttribute(
String name,
String typeName,
int type,
int size,
int precision,
boolean allowNulls) {
if (typeName != null) {
typeName = typeName.toLowerCase();
}
// all LOB types are returned by the driver as OTHER... must remap them manually
// (at least on MySQL 3.23)
if (type == Types.OTHER) {
if ("longblob".equals(typeName)) {
type = Types.BLOB;
}
else if ("mediumblob".equals(typeName)) {
type = Types.BLOB;
}
else if ("blob".equals(typeName)) {
type = Types.BLOB;
}
else if ("tinyblob".equals(typeName)) {
type = Types.VARBINARY;
}
else if ("longtext".equals(typeName)) {
type = Types.CLOB;
}
else if ("mediumtext".equals(typeName)) {
type = Types.CLOB;
}
else if ("text".equals(typeName)) {
type = Types.CLOB;
}
else if ("tinytext".equals(typeName)) {
type = Types.VARCHAR;
}
}
// types like "int unsigned" map to Long
else if (typeName != null && typeName.endsWith(" unsigned")) {
// per
// http://dev.mysql.com/doc/refman/5.0/en/connector-j-reference-type-conversions.html
if (typeName.equals("int unsigned")
|| typeName.equals("integer unsigned")
|| typeName.equals("mediumint unsigned")) {
type = Types.BIGINT;
}
// BIGINT UNSIGNED maps to BigInteger according to MySQL docs, but there is no
// JDBC mapping for BigInteger
}
return super.buildAttribute(name, typeName, type, size, precision, allowNulls);
}
/**
* Returns null, since views are not yet supported in MySQL. Views are available on
* newer versions of MySQL.
*/
public String tableTypeForView() {
return null;
}
/**
* Creates and returns a primary key generator. Overrides superclass implementation to
* return an instance of MySQLPkGenerator that does the correct table locking.
*/
protected PkGenerator createPkGenerator() {
return new MySQLPkGenerator();
}
/**
* Overrides super implementation to explicitly set table engine to InnoDB if FK
* constraints are supported by this adapter.
*/
public String createTable(DbEntity entity) {
String ddlSQL = super.createTable(entity);
// force InnoDB tables if constraints are enabled
if (supportsFkConstraints()) {
ddlSQL += " ENGINE=InnoDB";
}
return ddlSQL;
}
/**
* Customizes PK clause semantics to ensure that generated columns are in the
* beginning of the PK definition, as this seems to be a requirement for InnoDB
* tables.
*
* @since 1.2
*/
// See CAY-358 for details of the InnoDB problem
protected void createTableAppendPKClause(StringBuffer sqlBuffer, DbEntity entity) {
// must move generated to the front...
List pkList = new ArrayList(entity.getPrimaryKey());
Collections.sort(pkList, new PKComparator());
Iterator pkit = pkList.iterator();
if (pkit.hasNext()) {
sqlBuffer.append(", PRIMARY KEY (");
boolean firstPk = true;
while (pkit.hasNext()) {
if (firstPk)
firstPk = false;
else
sqlBuffer.append(", ");
DbAttribute at = (DbAttribute) pkit.next();
sqlBuffer.append(at.getName());
}
sqlBuffer.append(')');
}
// if FK constraints are supported, we must add indices to all FKs
// Note that according to MySQL docs, FK indexes are created automatically when
// constraint is defined, starting at MySQL 4.1.2
if (supportsFkConstraints()) {
Iterator relationships = entity.getRelationships().iterator();
while (relationships.hasNext()) {
DbRelationship relationship = (DbRelationship) relationships.next();
if (relationship.getJoins().size() > 0
&& relationship.isToPK()
&& !relationship.isToDependentPK()) {
sqlBuffer.append(", KEY (");
Iterator columns = relationship.getSourceAttributes().iterator();
DbAttribute column = (DbAttribute) columns.next();
sqlBuffer.append(column.getName());
while (columns.hasNext()) {
column = (DbAttribute) columns.next();
sqlBuffer.append(", ").append(column.getName());
}
sqlBuffer.append(")");
}
}
}
}
/**
* Appends AUTO_INCREMENT clause to the column definition for generated columns.
*/
protected void createTableAppendColumn(StringBuffer sqlBuffer, DbAttribute column) {
super.createTableAppendColumn(sqlBuffer, column);
if (column.isGenerated()) {
sqlBuffer.append(" AUTO_INCREMENT");
}
}
final class PKComparator implements Comparator {
public int compare(Object o1, Object o2) {
DbAttribute a1 = (DbAttribute) o1;
DbAttribute a2 = (DbAttribute) o2;
if (a1.isGenerated() != a2.isGenerated()) {
return a1.isGenerated() ? -1 : 1;
}
else {
return a1.getName().compareTo(a2.getName());
}
}
}
}
© 2015 - 2024 Weber Informatics LLC | Privacy Policy