Chapter 4 MySQL Cluster Connector for Java

The com.mysql.clusterj.SessionFactory is configured via properties, which identify the NDB Cluster that the application connects to:

    File propsFile = new File("clusterj.properties");
    InputStream inStream = new FileInputStream(propsFile);
    Properties props = new Properties();
    props.load(inStream);
    SessionFactory sessionFactory = ClusterJHelper.getSessionFactory(props);

Session The com.mysql.clusterj.Session represents the user's individual connection to the cluster. It contains methods for:

    Session session = sessionFactory.getSession();
    Employee existing = session.find(Employee.class, 1);
    if (existing != null) {
        session.remove(existing);
    }
    Employee newemp = session.newInstance(Employee.class);
    newemp.initialize(2, "Craig", 15, 146000.00);
    session.persist(newemp);

Transaction The com.mysql.clusterj.Transaction allows users to combine multiple operations into a single database transaction. It contains methods to:

    Transaction tx = session.currentTransaction();
    tx.begin();
    Employee existing = session.find(Employee.class, 1);
    Employee newemp = session.newInstance(Employee.class);
    newemp.initialize(2, "Craig", 146000.00);
    session.persist(newemp);
    tx.commit();

QueryBuilder The com.mysql.clusterj.query.QueryBuilder allows users to build queries. It contains methods to:

    QueryBuilder builder = session.getQueryBuilder();
    QueryDomainType<Employee> qemp = builder.createQueryDefinition(Employee.class);
    Predicate service = qemp.get("yearsOfService").greaterThan(qemp.param("service"));
    Predicate salary = qemp.get("salary").lessEqual(qemp.param("salaryCap"));
    qemp.where(service.and(salary));
    Query<Employee> query = session.createQuery(qemp);
    query.setParameter("service", 10);
    query.setParameter("salaryCap", 180000.00);
    List<Employee> results = query.getResultList();

 public class ClusterJDatastoreException extends, ClusterJException {
// Public Constructors  public ClusterJDatastoreException(String message);
  public ClusterJDatastoreException(String msg,
                                    int code,
                                    int mysqlCode,
                                    int status,
                                    int classification);
  public ClusterJDatastoreException(String message,
                                    Throwable t);
  public ClusterJDatastoreException(Throwable t);
// Public Methods  public int getClassification();
  public int getCode();
  public int getMysqlCode();
  public int getStatus();
}

Methods inherited from com.mysql.clusterj.ClusterJException: printStackTrace

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.1 ClusterJDatastoreException Class

Get the classification

Get the code

Get the mysql code

Get the status

 public static final class ClusterJDatastoreException.Classification extends, Enum<Classification> {
// Public Static Fields  public static final Classification ApplicationError ;
  public static final Classification ConstraintViolation ;
  public static final Classification FunctionNotImplemented ;
  public static final Classification InsufficientSpace ;
  public static final Classification InternalError ;
  public static final Classification InternalTemporary ;
  public static final Classification NoDataFound ;
  public static final Classification NoError ;
  public static final Classification NodeRecoveryError ;
  public static final Classification NodeShutdown ;
  public static final Classification OverloadError ;
  public static final Classification SchemaError ;
  public static final Classification SchemaObjectExists ;
  public static final Classification TemporaryResourceError ;
  public static final Classification TimeoutExpired ;
  public static final Classification UnknownErrorCode ;
  public static final Classification UnknownResultError ;
  public static final Classification UserDefinedError ;
// Public Static Methods  public static Classification lookup(int value);
  public static Classification valueOf(String name);
  public static Classification[] values();
}

Methods inherited from java.lang.Enum: compareTo , equals , getDeclaringClass , hashCode , name , ordinal , toString , valueOf

Methods inherited from java.lang.Object: getClass , notify , notifyAll , wait

Figure 4.2 ClusterJDatastoreException.Classification Class

Get the Classification enum for a value returned by ClusterJDatastoreException.getClassification().

 public class ClusterJException extends, RuntimeException {
// Public Constructors  public ClusterJException(String message);
  public ClusterJException(String message,
                           Throwable t);
  public ClusterJException(Throwable t);
// Public Methods  public synchronized void printStackTrace(PrintStream s);
}

Direct known subclasses: com.mysql.clusterj.ClusterJDatastoreException , com.mysql.clusterj.ClusterJFatalException , com.mysql.clusterj.ClusterJUserException

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , printStackTrace , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.3 ClusterJException Class

 public class ClusterJFatalException extends, ClusterJException {
// Public Constructors  public ClusterJFatalException(String string);
  public ClusterJFatalException(String string,
                                Throwable t);
  public ClusterJFatalException(Throwable t);
}

Direct known subclasses: com.mysql.clusterj.ClusterJFatalInternalException , com.mysql.clusterj.ClusterJFatalUserException

Methods inherited from com.mysql.clusterj.ClusterJException: printStackTrace

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.4 ClusterJFatalException Class

 public class ClusterJFatalInternalException extends, ClusterJFatalException {
// Public Constructors  public ClusterJFatalInternalException(String string);
  public ClusterJFatalInternalException(String string,
                                        Throwable t);
  public ClusterJFatalInternalException(Throwable t);
}

Methods inherited from com.mysql.clusterj.ClusterJException: printStackTrace

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.5 ClusterJFatalInternalException Class

 public class ClusterJFatalUserException extends, ClusterJFatalException {
// Public Constructors  public ClusterJFatalUserException(String string);
  public ClusterJFatalUserException(String string,
                                    Throwable t);
  public ClusterJFatalUserException(Throwable t);
}

Methods inherited from com.mysql.clusterj.ClusterJException: printStackTrace

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.6 ClusterJFatalUserException Class

 public class ClusterJHelper {
// Public Constructors  public ClusterJHelper();
// Public Static Methods  public static boolean getBooleanProperty(String propertyName,
                                           String def);
  public static T getServiceInstance(Class<T> cls);
  public static T getServiceInstance(Class<T> cls,
                                     ClassLoader loader);
  public static T getServiceInstance(Class<T> cls,
                                     String implementationClassName);
  public static T getServiceInstance(Class<T> cls,
                                     String implementationClassName,
                                     ClassLoader loader);
  public static List<T> getServiceInstances(Class<T> cls,
                                            ClassLoader loader,
                                            StringBuffer errorMessages);
  public static SessionFactory getSessionFactory(Map props);
  public static SessionFactory getSessionFactory(Map props,
                                                 ClassLoader loader);
  public static String getStringProperty(String propertyName,
                                         String def);
  public static Dbug newDbug();
}

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , toString , wait

Figure 4.7 ClusterJHelper Class

Get the named boolean property from either the environment or system properties. If the property is not 'true' then return false.

Locate a service implementation by services lookup of the context class loader.

Locate a service implementation for a service by services lookup of a specific class loader. The first service instance found is returned.

Locate a service implementation for a service. If the implementation name is not null, use it instead of looking up. If the implementation class is not loadable or does not implement the interface, throw an exception. Use the ClusterJHelper class loader to find the service.

Locate a service implementation for a service. If the implementation name is not null, use it instead of looking up. If the implementation class is not loadable or does not implement the interface, throw an exception.

Locate all service implementations by services lookup of a specific class loader. Implementations in the services file are instantiated and returned. Failed instantiations are remembered in the errorMessages buffer.

Locate a SessionFactory implementation by services lookup. The class loader used is the thread's context class loader.

Locate a SessionFactory implementation by services lookup of a specific class loader. The properties are a Map that might contain implementation-specific properties plus standard properties.

Get the named String property from either the environment or system properties.

Return a new Dbug instance.

 public class ClusterJUserException extends, ClusterJException {
// Public Constructors  public ClusterJUserException(String message);
  public ClusterJUserException(String message,
                               Throwable t);
  public ClusterJUserException(Throwable t);
}

Methods inherited from com.mysql.clusterj.ClusterJException: printStackTrace

Methods inherited from java.lang.Throwable: addSuppressed , fillInStackTrace , getCause , getLocalizedMessage , getMessage , getStackTrace , getSuppressed , initCause , setStackTrace , toString

Methods inherited from java.lang.Object: equals , getClass , hashCode , notify , notifyAll , wait

Figure 4.8 ClusterJUserException Class

Return the charset name.

Return the type of the column.

Return whether this column is a partition key column.

Return whether this column is a primary key column.

Return the java type of the column.

Return the maximum number of bytes that can be stored in the column after translating the characters using the character set.

Return the name of the column.

Return whether this column is nullable.

Return the column number. This number is used as the first parameter in the get and set methods of DynamicColumn.

Return the precision of the column.

Return the scale of the column.

 public final class ColumnType extends, Enum<ColumnType> {
// Public Static Fields  public static final ColumnType Bigint ;
  public static final ColumnType Bigunsigned ;
  public static final ColumnType Binary ;
  public static final ColumnType Bit ;
  public static final ColumnType Blob ;
  public static final ColumnType Char ;
  public static final ColumnType Date ;
  public static final ColumnType Datetime ;
  public static final ColumnType Datetime2 ;
  public static final ColumnType Decimal ;
  public static final ColumnType Decimalunsigned ;
  public static final ColumnType Double ;
  public static final ColumnType Float ;
  public static final ColumnType Int ;
  public static final ColumnType Longvarbinary ;
  public static final ColumnType Longvarchar ;
  public static final ColumnType Mediumint ;
  public static final ColumnType Mediumunsigned ;
  public static final ColumnType Olddecimal ;
  public static final ColumnType Olddecimalunsigned ;
  public static final ColumnType Smallint ;
  public static final ColumnType Smallunsigned ;
  public static final ColumnType Text ;
  public static final ColumnType Time ;
  public static final ColumnType Time2 ;
  public static final ColumnType Timestamp ;
  public static final ColumnType Timestamp2 ;
  public static final ColumnType Tinyint ;
  public static final ColumnType Tinyunsigned ;
  public static final ColumnType Undefined ;
  public static final ColumnType Unsigned ;
  public static final ColumnType Varbinary ;
  public static final ColumnType Varchar ;
  public static final ColumnType Year ;
// Public Static Methods  public static ColumnType valueOf(String name);
  public static ColumnType[] values();
}

Methods inherited from java.lang.Enum: compareTo , equals , getDeclaringClass , hashCode , name , ordinal , toString , valueOf

Methods inherited from java.lang.Object: getClass , notify , notifyAll , wait

Figure 4.10 ColumnType Class

 public interface Constants {
// Public Static Fields  public static final String DEFAULT_PROPERTY_CLUSTER_BYTE_BUFFER_POOL_SIZES = "256, 10240, 102400, 1048576";
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_BATCH_SIZE = 10;
  public static final long DEFAULT_PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_START = 1L;
  public static final long DEFAULT_PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_STEP = 1L;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_DELAY = 5;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_RETRIES = 4;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_TIMEOUT_AFTER = 20;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_TIMEOUT_BEFORE = 30;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_TIMEOUT_MGM = 30000;
  public static final int DEFAULT_PROPERTY_CLUSTER_CONNECT_VERBOSE = 0;
  public static final String DEFAULT_PROPERTY_CLUSTER_DATABASE = "test";
  public static final int DEFAULT_PROPERTY_CLUSTER_MAX_TRANSACTIONS = 4;
  public static final int DEFAULT_PROPERTY_CONNECTION_POOL_SIZE = 1;
  public static final String ENV_CLUSTERJ_LOGGER_FACTORY_NAME = "CLUSTERJ_LOGGER_FACTORY";
  public static final String PROPERTY_CLUSTER_BYTE_BUFFER_POOL_SIZES = "com.mysql.clusterj.byte.buffer.pool.sizes";
  public static final String PROPERTY_CLUSTER_CONNECTION_SERVICE = "com.mysql.clusterj.connection.service";
  public static final String PROPERTY_CLUSTER_CONNECTSTRING = "com.mysql.clusterj.connectstring";
  public static final String PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_BATCH_SIZE = "com.mysql.clusterj.connect.autoincrement.batchsize";
  public static final String PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_START = "com.mysql.clusterj.connect.autoincrement.offset";
  public static final String PROPERTY_CLUSTER_CONNECT_AUTO_INCREMENT_STEP = "com.mysql.clusterj.connect.autoincrement.increment";
  public static final String PROPERTY_CLUSTER_CONNECT_DELAY = "com.mysql.clusterj.connect.delay";
  public static final String PROPERTY_CLUSTER_CONNECT_RETRIES = "com.mysql.clusterj.connect.retries";
  public static final String PROPERTY_CLUSTER_CONNECT_TIMEOUT_AFTER = "com.mysql.clusterj.connect.timeout.after";
  public static final String PROPERTY_CLUSTER_CONNECT_TIMEOUT_BEFORE = "com.mysql.clusterj.connect.timeout.before";
  public static final String PROPERTY_CLUSTER_CONNECT_TIMEOUT_MGM = "com.mysql.clusterj.connect.timeout.mgm";
  public static final String PROPERTY_CLUSTER_CONNECT_VERBOSE = "com.mysql.clusterj.connect.verbose";
  public static final String PROPERTY_CLUSTER_DATABASE = "com.mysql.clusterj.database";
  public static final String PROPERTY_CLUSTER_MAX_TRANSACTIONS = "com.mysql.clusterj.max.transactions";
  public static final String PROPERTY_CONNECTION_POOL_NODEIDS = "com.mysql.clusterj.connection.pool.nodeids";
  public static final String PROPERTY_CONNECTION_POOL_SIZE = "com.mysql.clusterj.connection.pool.size";
  public static final String PROPERTY_DEFER_CHANGES = "com.mysql.clusterj.defer.changes";
  public static final String PROPERTY_JDBC_DRIVER_NAME = "com.mysql.clusterj.jdbc.driver";
  public static final String PROPERTY_JDBC_PASSWORD = "com.mysql.clusterj.jdbc.password";
  public static final String PROPERTY_JDBC_URL = "com.mysql.clusterj.jdbc.url";
  public static final String PROPERTY_JDBC_USERNAME = "com.mysql.clusterj.jdbc.username";
  public static final String SESSION_FACTORY_SERVICE_CLASS_NAME = "com.mysql.clusterj.SessionFactoryService";
  public static final String SESSION_FACTORY_SERVICE_FILE_NAME = "META-INF/services/com.mysql.clusterj.SessionFactoryService";
}

Figure 4.11 Constants Class

The default value of the byte buffer pool sizes property: 256, 10K, 100K, 1M

The default value of the connection delay property

The default value of the connection autoincrement offset property

The default value of the connection delay property

The default value of the connection delay property

The default value of the connection retries property

The default value of the connection timeout after property

The default value of the connection timeout before property

The default value of the connection timeout mgm property

The default value of the connection verbose property

The default value of the database property

The default value of the maximum number of transactions property

The default value of the connection pool size property

The name of the environment variable to set the logger factory

The name of the byte buffer pool sizes property. To disable buffer pooling for blob objects, set the value of this property to "1". With this setting, buffers will be allocated and freed (and cleaned if possible) immediately after being used for blob data transfer.

The name of the connection autoincrement batch size property. For details, see Ndb_cluster_connection::connect()

The name of the connection autoincrement offset property. For details, see Ndb_cluster_connection::connect()

The name of the connection autoincrement increment property. For details, see Ndb_cluster_connection::connect()

The name of the connection delay property. For details, see Ndb_cluster_connection::connect()

The name of the connection retries property. For details, see Ndb_cluster_connection::connect()

The name of the connection timeout after property. For details, see Ndb_cluster_connection::wait_until_ready()

The name of the connection timeout before property. For details, see Ndb_cluster_connection::wait_until_ready()

The name of the initial timeout for cluster connection to connect to MGM before connecting to data nodes Ndb_cluster_connection::set_timeout()

The name of the connection verbose property. For details, see Ndb_cluster_connection::connect()

The name of the connection service property

The name of the connection string property. For details, see Ndb_cluster_connection constructor

The name of the database property. For details, see the catalogName parameter in the Ndb constructor. Ndb constructor

The name of the maximum number of transactions property. For details, see Ndb::init()

The name of the connection pool node ids property. There is no default. This is the list of node ids to force the connections to be assigned to specific node ids. If this property is specified and connection pool size is not the default, the number of node ids of the list must match the connection pool size, or the number of node ids must be 1 and node ids will be assigned to connections starting with the specified node id.

The name of the connection pool size property. This is the number of connections to create in the connection pool. The default is 1 (all sessions share the same connection; all requests for a SessionFactory with the same connect string and database will share a single SessionFactory). A setting of 0 disables pooling; each request for a SessionFactory will receive its own unique SessionFactory.

The flag for deferred inserts, deletes, and updates

The name of the jdbc driver

The jdbc password

The jdbc url

The jdbc username

The name of the session factory service interface

The name of the files with names of implementation classes for session factory service

 public interface Dbug {
// Public Methods  public abstract Dbug append(String fileName);
  public abstract Dbug debug(String string);
  public abstract Dbug debug(String[] strings);
  public abstract Dbug flush();
  public abstract String get();
  public abstract Dbug output(String fileName);
  public abstract void pop();
  public abstract void print(String keyword,
                             String message);
  public abstract void push();
  public abstract void push(String state);
  public abstract void set();
  public abstract void set(String state);
  public abstract Dbug trace();
}

Figure 4.12 Dbug Class

Specify the file name for debug output (append).

Set the list of debug keywords.

Set the list of debug keywords.

Force flush after each output operation.

Return the current state.

Specify the file name for debug output (overwrite).

Pop the current state. The new state will be the previously pushed state.

Print debug message.

Push the current state as defined by the methods.

Push the current state and set the parameter as the new state.

Set the current state as defined by the methods.

Set the current state from the parameter.

Set the trace flag.

 public final class LockMode extends, Enum<LockMode> {
// Public Static Fields  public static final LockMode EXCLUSIVE ;
  public static final LockMode READ_COMMITTED ;
  public static final LockMode SHARED ;
// Public Static Methods  public static LockMode valueOf(String name);
  public static LockMode[] values();
}

Methods inherited from java.lang.Enum: compareTo , equals , getDeclaringClass , hashCode , name , ordinal , toString , valueOf

Methods inherited from java.lang.Object: getClass , notify , notifyAll , wait

Figure 4.15 LockMode Class

 public interface Query<E> {
// Public Static Fields  public static final String INDEX_USED = "IndexUsed";
  public static final String SCAN_TYPE = "ScanType";
  public static final String SCAN_TYPE_INDEX_SCAN = "INDEX_SCAN";
  public static final String SCAN_TYPE_PRIMARY_KEY = "PRIMARY_KEY";
  public static final String SCAN_TYPE_TABLE_SCAN = "TABLE_SCAN";
  public static final String SCAN_TYPE_UNIQUE_KEY = "UNIQUE_KEY";
// Public Methods  public abstract int deletePersistentAll();
  public abstract Results<E> execute(Object parameter);
  public abstract Results<E> execute(Object[] parameters);
  public abstract Results<E> execute(Map<String, ?> parameters);
  public abstract Map<String, Object> explain();
  public abstract List<E> getResultList();
  public abstract void setLimits(long skip,
                                 long limit);
  public abstract void setOrdering(Ordering ordering,
                                   String[] orderingFields);
  public abstract void setParameter(String parameterName,
                                    Object value);
}

Figure 4.16 Query Class

The query explain index used key

The query explain scan type key

The query explain scan type value for index scan

The query explain scan type value for primary key

The query explain scan type value for table scan

The query explain scan type value for unique key

Delete the instances that satisfy the query criteria.

Execute the query with one or more named parameters. Parameters are resolved by name.

Execute the query with one or more parameters. Parameters are resolved in the order they were declared in the query.

Execute the query with exactly one parameter.

Explain how this query will be or was executed. If called before binding all parameters, throws ClusterJUserException. Return a map of key:value pairs that explain how the query will be or was executed. Details can be obtained by calling toString on the value. The following keys are returned:

Get the results as a list.

Set limits on results to return. The execution of the query is modified to return only a subset of results. If the filter would normally return 100 instances, skip is set to 50, and limit is set to 40, then the first 50 results that would have been returned are skipped, the next 40 results are returned and the remaining 10 results are ignored.

Skip must be greater than or equal to 0. Limit must be greater than or equal to 0. Limits may not be used with deletePersistentAll.

Set ordering for the results of this query. The execution of the query is modified to use an index previously defined.

If an "in" predicate is used, each element in the parameter defines a separate range, and ordering is performed within that range. There may be a better (more efficient) index based on the filter, but specifying the ordering will force the query to use an index that contains the ordering fields.

Set the value of a parameter. If called multiple times for the same parameter, silently replace the value.

 public static final class Query.Ordering extends, Enum<Ordering> {
// Public Static Fields  public static final Ordering ASCENDING ;
  public static final Ordering DESCENDING ;
// Public Static Methods  public static Ordering valueOf(String name);
  public static Ordering[] values();
}

Methods inherited from java.lang.Enum: compareTo , equals , getDeclaringClass , hashCode , name , ordinal , toString , valueOf

Methods inherited from java.lang.Object: getClass , notify , notifyAll , wait

Figure 4.17 Query.Ordering Class

 public interface Results<E> extends, Iterable<E> {
// Public Methods  public abstract Iterator<E> iterator();
}

Figure 4.18 Results Class

Specified by: Method iterator in interface Iterable

Get an iterator over the results of a query.

 public interface Session {
// Public Methods  public abstract void close();
  public abstract Query<T> createQuery(QueryDefinition<T> qd);
  public abstract Transaction currentTransaction();
  public abstract void deletePersistent(Class<T> cls,
                                        Object key);
  public abstract void deletePersistent(Object instance);
  public abstract int deletePersistentAll(Class<T> cls);
  public abstract void deletePersistentAll(Iterable<?> instances);
  public abstract T find(Class<T> cls,
                         Object key);
  public abstract void flush();
  public abstract Boolean found(Object instance);
  public abstract QueryBuilder getQueryBuilder();
  public abstract boolean isClosed();
  public abstract T load(T instance);
  public abstract T makePersistent(T instance);
  public abstract Iterable<?> makePersistentAll(Iterable<?> instances);
  public abstract void markModified(Object instance,
                                    String fieldName);
  public abstract T newInstance(Class<T> cls);
  public abstract T newInstance(Class<T> cls,
                                Object key);
  public abstract void persist(Object instance);
  public abstract T release(T obj);
  public abstract void remove(Object instance);
  public abstract T savePersistent(T instance);
  public abstract Iterable<?> savePersistentAll(Iterable<?> instances);
  public abstract void setLockMode(LockMode lockmode);
  public abstract void setPartitionKey(Class<?> cls,
                                       Object key);
  public abstract String unloadSchema(Class<?> cls);
  public abstract void updatePersistent(Object instance);
  public abstract void updatePersistentAll(Iterable<?> instances);
}

Figure 4.19 Session Class

Close this session.

Create a Query from a QueryDefinition.

Get the current com.mysql.clusterj.Transaction.

Delete an instance of a class from the database given its primary key. For single-column keys, the key parameter is a wrapper (e.g. Integer). For multi-column keys, the key parameter is an Object[] in which elements correspond to the primary keys in order as defined in the schema.

Delete the instance from the database. Only the id field is used to determine which instance is to be deleted. If the instance does not exist in the database, an exception is thrown.

Delete all instances of this class from the database. No exception is thrown even if there are no instances in the database.

Delete all parameter instances from the database.

Find a specific instance by its primary key. The key must be of the same type as the primary key defined by the table corresponding to the cls parameter. The key parameter is the wrapped version of the primitive type of the key, e.g. Integer for INT key types, Long for BIGINT key types, or String for char and varchar types. For multi-column primary keys, the key parameter is an Object[], each element of which is a component of the primary key. The elements must be in the order of declaration of the columns (not necessarily the order defined in the CONSTRAINT ... PRIMARY KEY clause) of the CREATE TABLE statement.

Flush deferred changes to the back end. Inserts, deletes, loads, and updates are sent to the back end.

Was the row corresponding to this instance found in the database?

Get a QueryBuilder.

Is this session closed?

Load the instance from the database into memory. Loading is asynchronous and will be executed when an operation requiring database access is executed: find, flush, or query. The instance must have been returned from find or query; or created via session.newInstance and its primary key initialized.

Insert the instance into the database. If the instance already exists in the database, an exception is thrown.

Insert the instances into the database.

Mark the field in the object as modified so it is flushed.

Create an instance of an interface or dynamic class that maps to a table.

Create an instance of an interface or dynamic class that maps to a table and set the primary key of the new instance. The new instance can be used to create, delete, or update a record in the database.

Insert the instance into the database. This method has identical semantics to makePersistent.

Release resources associated with an instance. The instance must be a domain object obtained via session.newInstance(T.class), find(T.class), or query; or Iterable, or array T[]. Resources released can include direct buffers used to hold instance data. Released resources may be returned to a pool.

Delete the instance from the database. This method has identical semantics to deletePersistent.

Save the instance in the database without checking for existence. The id field is used to determine which instance is to be saved. If the instance exists in the database it will be updated. If the instance does not exist, it will be created.

Update all parameter instances in the database.

Set the lock mode for read operations. This will take effect immediately and will remain in effect until this session is closed or this method is called again.

Set the partition key for the next transaction. The key must be of the same type as the primary key defined by the table corresponding to the cls parameter. The key parameter is the wrapped version of the primitive type of the key, e.g. Integer for INT key types, Long for BIGINT key types, or String for char and varchar types. For multi-column primary keys, the key parameter is an Object[], each element of which is a component of the primary key. The elements must be in the order of declaration of the columns (not necessarily the order defined in the CONSTRAINT ... PRIMARY KEY clause) of the CREATE TABLE statement.

Unload the schema definition for a class. This must be done after the schema definition has changed in the database due to an alter table command. The next time the class is used the schema will be reloaded.

Update the instance in the database without necessarily retrieving it. The id field is used to determine which instance is to be updated. If the instance does not exist in the database, an exception is thrown. This method cannot be used to change the primary key.

Update all parameter instances in the database.

 public interface SessionFactory {
// Public Methods  public abstract void close();
  public abstract List<Integer> getConnectionPoolSessionCounts();
  public abstract Session getSession();
  public abstract Session getSession(Map properties);
}

Figure 4.20 SessionFactory Class