## org.springframework.jdbc.datasource
Class ConnectionHolder

    java.lang.Object
      org.springframework.transaction.support.ResourceHolderSupport
          org.springframework.jdbc.datasource.ConnectionHolder

All Implemented Interfaces:
  ResourceHolder

    public class ConnectionHolder

extends ResourceHolderSupport

Connection holder, wrapping a JDBC Connection. `DataSourceTransactionManager` binds instances of this class to the thread, for a specific DataSource.

Inherits rollback-only support for nested JDBC transactions and reference count functionality from the base class.

Note: This is an SPI class, not intended to be used by applications.

Since:
  06.05.2003
Author:
  Juergen Hoeller
See Also:
  `DataSourceTransactionManager`, `DataSourceUtils`

Field Summary
`static String` `SAVEPOINT_NAME_PREFIX`

Constructor Summary
`ConnectionHolder(Connection connection)` Create a new ConnectionHolder for the given JDBC Connection, wrapping it with a `SimpleConnectionHandle`, assuming that there is no ongoing transaction.
`ConnectionHolder(Connection connection, boolean transactionActive)` Create a new ConnectionHolder for the given JDBC Connection, wrapping it with a `SimpleConnectionHandle`.
`ConnectionHolder(ConnectionHandle connectionHandle)` Create a new ConnectionHolder for the given ConnectionHandle.

Method Summary
`void` `clear()` Clear the transactional state of this resource holder.
`Savepoint` `createSavepoint()` Create a new JDBC 3.0 Savepoint for the current Connection, using generated savepoint names that are unique for the Connection.
`Connection` `getConnection()` Return the current Connection held by this ConnectionHolder.
`ConnectionHandle` `getConnectionHandle()` Return the ConnectionHandle held by this ConnectionHolder.
`protected boolean` `hasConnection()` Return whether this holder currently has a Connection.
`protected boolean` `isTransactionActive()` Return whether this holder represents an active, JDBC-managed transaction.
`void` `released()` Releases the current Connection held by this ConnectionHolder.
`protected void` `setConnection(Connection connection)` Override the existing Connection handle with the given Connection.
`protected void` `setTransactionActive(boolean transactionActive)` Set whether this holder represents an active, JDBC-managed transaction.
`boolean` `supportsSavepoints()` Return whether JDBC 3.0 Savepoints are supported.

Methods inherited from class org.springframework.transaction.support.ResourceHolderSupport
`getDeadline, getTimeToLiveInMillis, getTimeToLiveInSeconds, hasTimeout, isOpen, isRollbackOnly, isSynchronizedWithTransaction, isVoid, requested, reset, setRollbackOnly, setSynchronizedWithTransaction, setTimeoutInMillis, setTimeoutInSeconds, unbound`

Methods inherited from class java.lang.Object
`clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait`

Field Detail

### SAVEPOINT_NAME_PREFIX

    public static final String SAVEPOINT_NAME_PREFIX

See Also:
  Constant Field Values

Constructor Detail

### ConnectionHolder

    public ConnectionHolder(ConnectionHandle connectionHandle)

  Create a new ConnectionHolder for the given ConnectionHandle.

  Parameters:
    `connectionHandle` - the ConnectionHandle to hold

### ConnectionHolder

    public ConnectionHolder(Connection connection)

  Create a new ConnectionHolder for the given JDBC Connection, wrapping it with a `SimpleConnectionHandle`, assuming that there is no ongoing transaction.

  Parameters:
    `connection` - the JDBC Connection to hold
  See Also:
    `SimpleConnectionHandle`, `ConnectionHolder(java.sql.Connection, boolean)`

### ConnectionHolder

    public ConnectionHolder(Connection connection,
                            boolean transactionActive)

  Create a new ConnectionHolder for the given JDBC Connection, wrapping it with a `SimpleConnectionHandle`.

  Parameters:
    `connection` - the JDBC Connection to hold
    `transactionActive` - whether the given Connection is involved in an ongoing transaction
  See Also:
    `SimpleConnectionHandle`

Method Detail

### getConnectionHandle

    public ConnectionHandle getConnectionHandle()

  Return the ConnectionHandle held by this ConnectionHolder.

### hasConnection

    protected boolean hasConnection()

  Return whether this holder currently has a Connection.

### setTransactionActive

    protected void setTransactionActive(boolean transactionActive)

  Set whether this holder represents an active, JDBC-managed transaction.

  See Also:
    `DataSourceTransactionManager`

### isTransactionActive

    protected boolean isTransactionActive()

  Return whether this holder represents an active, JDBC-managed transaction.

### setConnection

    protected void setConnection(Connection connection)

  Override the existing Connection handle with the given Connection. Reset the handle if given `null`.

  Used for releasing the Connection on suspend (with a `null` argument) and setting a fresh Connection on resume.

### getConnection

    public Connection getConnection()

  Return the current Connection held by this ConnectionHolder.

  This will be the same Connection until `released` gets called on the ConnectionHolder, which will reset the held Connection, fetching a new Connection on demand.

  See Also:
    `ConnectionHandle.getConnection()`, `released()`

### supportsSavepoints

    public boolean supportsSavepoints()
                               throws SQLException

  Return whether JDBC 3.0 Savepoints are supported. Caches the flag for the lifetime of this ConnectionHolder.

  Throws:
    `SQLException` - if thrown by the JDBC driver

### createSavepoint

    public Savepoint createSavepoint()
                              throws SQLException

  Create a new JDBC 3.0 Savepoint for the current Connection, using generated savepoint names that are unique for the Connection.

  Returns:
    the new Savepoint
  Throws:
    `SQLException` - if thrown by the JDBC driver

### released

    public void released()

  Releases the current Connection held by this ConnectionHolder.

  This is necessary for ConnectionHandles that expect "Connection borrowing", where each returned Connection is only temporarily leased and needs to be returned once the data operation is done, to make the Connection available for other operations within the same transaction. This is the case with JDO 2.0 DataStoreConnections, for example.

  Overrides:
    `released` in class `ResourceHolderSupport`
  See Also:
    `DefaultJdoDialect.getJdbcConnection(javax.jdo.PersistenceManager, boolean)`

### clear

    public void clear()

  Description copied from class: `ResourceHolderSupport`
  Clear the transactional state of this resource holder.

  Overrides:
    `clear` in class `ResourceHolderSupport`