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## com.beasys.commerce.util
Class JDBCSequencer

    java.lang.Object
      com.beasys.commerce.util.JDBCSequencer

All Implemented Interfaces:
  Sequencer

Deprecated. Use `com.bea.p13n.util.jdbc.Sequencer` and `com.bea.p13n.util.jdbc.SequencerFactory`

public class JDBCSequencer
extends Object
implements Sequencer

The JDBCSequencer class is a portable implementation for generating unique sequence numbers. JDBCSequencer uses a caching strategy where a block of sequence numbers is allocated in memory. When the block of sequence numbers is exhausted, JDBCSequencer obtains a new range of sequence numbers from the database. This approach has the advantage of minimizing the database access but it can create sequence numbers to be skipped if the server is restarted.

This implementation uses the WLCS_SEQUENCER table to maintain the current values of the different sequences. Each sequence is represented by a row in the WLCS_SEQUENCER and a row is automatically inserted for a sequence that does not exists already.

When allocating a new block of sequence numbers, JDBCSequencer uses a retry loop for obtaining an application lock (IS_LOCKED column in WLCS_SEQUENCER) before incrementing the current value of a sequence. Two properties can be defined in the weblogiccommerce.properties file to control the number of retries and the datasource name to use for obtaining a database connection:

- `commerce.jdbcSequencer.maxRetry` default value is 5 (1 second wait each retry)
- `commerce.jdbcSequencer.dataSource.name` default value is "weblogic.jdbc.jts.commercePool"

Note:JDBSequencer must run in WebLogic because it must suspend the current transaction when allocating a new block of sequence numbers.

See Also:
  `Sequencer`, `SequencerFactory`

Field Summary
`static long` | `DEFAULT_CACHE_SIZE` Deprecated.
`static String` | `DEFAULT_SEQUENCE_NAME` Deprecated.
`static String` | `DEFAULT_SEQUENCER_DATASOURCE_NAME` Deprecated.
`static String` | `DEFAULT_SEQUENCER_NAME` Deprecated.
`static long` | `DEFAULT_STEP_SIZE` Deprecated.
`static String` | `SEQUENCE_LOCK_IDENTIFIER` Deprecated.
`static String` | `SEQUENCE_NAME_IDENTIFIER` Deprecated.
`static String` | `SEQUENCE_VALUE_IDENTIFIER` Deprecated.
`static String` | `SEQUENCER_DATASOURCE_NAME_PROPERTY` Deprecated.
`static String` | `SEQUENCER_MAX_RETRY_PROPERTY` Deprecated.

Constructor Summary
`JDBCSequencer()` Deprecated. Default constructor.
`JDBCSequencer(String sequencerName, String sequenceName)` Deprecated. Creates a new `JDBCSequencer` with the supplied sequencer name and managed sequence name.
`JDBCSequencer(String sequencerName, String sequenceName, long cacheSize)` Deprecated. Creates a new `JDBCSequencer` with the supplied sequencer name, managed sequence name, and cache size.
`JDBCSequencer(String sequencerName, String sequenceName, long cacheSize, long stepSize)` Deprecated. Creates a new `JDBCSequencer` with the supplied sequencer name, managed sequence name, cache size, and step size.

Method Summary
`protected void` | `allocateSequenceBlock()` Deprecated. Allocates a new block of sequence numbers from the database.
`protected void` | `cleanUpResources()` Deprecated. Closes any open DB resources.
`long` | `getCacheSize()` Deprecated. Returns the cache size.
`long` | `getCurrent()` Deprecated. Gets the current sequence number associated with this sequencer.
`long` | `getCurrent(Connection databaseConnection)` Deprecated. JDBCSequencer must allocate the sequence block using a separate transaction because the database updates can be undone if a rollback occurs on the passed connection. Replaced by `getNext()`
`long` | `getIncrementAmount()` Deprecated. Replaced by getCacheSize
`long` | `getNext()` Deprecated. Gets the next sequence number.
`long` | `getNext(Connection databaseConnection)` Deprecated. JDBCSequencer must allocate the sequence block using a separate transaction because the database updates can be undone if a rollback occurs on the passed connection. Replaced by `getNext()`
`String` | `getSequenceName()` Deprecated. Returns the name of the sequence that is managed by this sequencer.
`String` | `getSequencerName()` Deprecated. Returns the name of this sequencer.
`long` | `getStepSize()` Deprecated. Returns the step size.
`void` | `setCacheSize(long cacheSize)` Deprecated. Sets the cache size.
`void` | `setIncrementAmount(long incrementAmount)` Deprecated. Replaced by setCacheSize
`void` | `setSequenceName(String sequenceName)` Deprecated. Sets the name of the sequence that is managed by this sequencer.
`void` | `setSequencerName(String sequencerName)` Deprecated. Sets the name of this sequencer.
`void` | `setStepSize(long stepSize)` Deprecated. Sets the step size.

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

Field Detail

### DEFAULT_CACHE_SIZE

    public static final long DEFAULT_CACHE_SIZE

  Deprecated.
  See Also:
    Constant Field Values

### DEFAULT_SEQUENCE_NAME

    public static final String DEFAULT_SEQUENCE_NAME

  Deprecated.
  See Also:
    Constant Field Values

### DEFAULT_SEQUENCER_DATASOURCE_NAME

    public static final String DEFAULT_SEQUENCER_DATASOURCE_NAME

  Deprecated.
  See Also:
    Constant Field Values

### DEFAULT_SEQUENCER_NAME

    public static final String DEFAULT_SEQUENCER_NAME

  Deprecated.
  See Also:
    Constant Field Values

### DEFAULT_STEP_SIZE

    public static final long DEFAULT_STEP_SIZE

  Deprecated.
  See Also:
    Constant Field Values

### SEQUENCE_LOCK_IDENTIFIER

    public static final String SEQUENCE_LOCK_IDENTIFIER

  Deprecated.
  See Also:
    Constant Field Values

### SEQUENCE_NAME_IDENTIFIER

    public static final String SEQUENCE_NAME_IDENTIFIER

  Deprecated.
  See Also:
    Constant Field Values

### SEQUENCE_VALUE_IDENTIFIER

    public static final String SEQUENCE_VALUE_IDENTIFIER

  Deprecated.
  See Also:
    Constant Field Values

### SEQUENCER_DATASOURCE_NAME_PROPERTY

    public static final String SEQUENCER_DATASOURCE_NAME_PROPERTY

  Deprecated.
  See Also:
    Constant Field Values

### SEQUENCER_MAX_RETRY_PROPERTY

    public static final String SEQUENCER_MAX_RETRY_PROPERTY

  Deprecated.
  See Also:
    Constant Field Values

Constructor Detail

### JDBCSequencer

    public JDBCSequencer()

  Deprecated.
  Default constructor.

### JDBCSequencer

    public JDBCSequencer(String sequencerName,
                         String sequenceName)

  Deprecated.
  Creates a new `JDBCSequencer` with the supplied sequencer name and managed sequence name.

### JDBCSequencer

    public JDBCSequencer(String sequencerName,
                         String sequenceName,
                         long cacheSize)

  Deprecated.
  Creates a new `JDBCSequencer` with the supplied sequencer name, managed sequence name, and cache size.

### JDBCSequencer

    public JDBCSequencer(String sequencerName,
                         String sequenceName,
                         long cacheSize,
                         long stepSize)

  Deprecated.
  Creates a new `JDBCSequencer` with the supplied sequencer name, managed sequence name, cache size, and step size.

Method Detail

### allocateSequenceBlock

    protected final void allocateSequenceBlock()
                                        throws SQLException

  Deprecated.
  Allocates a new block of sequence numbers from the database. If a transaction is in progress, it is suspended during the database updates required for incrementing the current value of the sequence and resumed after.

  Throws:
    ``SQLException`` - on error.
    `SQLException`

### cleanUpResources

    protected final void cleanUpResources()

  Deprecated.
  Closes any open DB resources.

### getCacheSize

    public long getCacheSize()

  Deprecated.
  Returns the cache size. The cache size defines how often the sequencer will allocate a block of unique sequence numbers from the database. When the sequencer exhausts its supplied of allocated numbers, it will allocate a new sequence of numbers from the database.

  Specified by:
    `getCacheSize` in interface `Sequencer`
  Returns:
    The cache size.

### getCurrent

    public long getCurrent()
                    throws SQLException

  Deprecated.
  Gets the current sequence number associated with this sequencer.

  Throws:
    ``SQLException`` - on error.
    `SQLException`

### getCurrent

    public long getCurrent(Connection databaseConnection)
                    throws SQLException

  Deprecated. JDBCSequencer must allocate the sequence block using a separate transaction because the database updates can be undone if a rollback occurs on the passed connection. Replaced by `getNext()`

  Gets the current sequence number associated with this sequencer.

  Specified by:
    `getCurrent` in interface `Sequencer`
  Parameters:
    `databaseConnection` - The database connection used to generate the next sequence number.
  Throws:
    ``SQLException`` - on error.
    `SQLException`

### getIncrementAmount

    public long getIncrementAmount()

  Deprecated. Replaced by getCacheSize

  Returns the increment amount. The increment amount defines how often the sequencer will allocate a block of unique sequence numbers from the database. When the sequencer exhausts its supplied of allocated numbers, it will allocate a new sequence of numbers from the database.

  Specified by:
    `getIncrementAmount` in interface `Sequencer`
  Returns:
    The increment amount.
  See Also:
    `getCacheSize()`

### getNext

    public long getNext()
                 throws SQLException

  Deprecated.
  Gets the next sequence number. A new block of sequence numbers is allocated if the cache of numbers is exhausted.

  Returns:
    the next sequence number
  Throws:
    ``SQLException`` - on error.
    `SQLException`

### getNext

    public long getNext(Connection databaseConnection)
                 throws SQLException

  Deprecated. JDBCSequencer must allocate the sequence block using a separate transaction because the database updates can be undone if a rollback occurs on the passed connection. Replaced by `getNext()`

  Gets the next sequence number using the supplied database connection. The database connection will not be automatically closed upon method return. This class is thread safe.

  Specified by:
    `getNext` in interface `Sequencer`
  Parameters:
    `databaseConnection` - The database connection used to generate the next sequence number.
  Throws:
    ``SQLException`` - on error.
    `SQLException`

### getSequenceName

    public String getSequenceName()

  Deprecated.
  Returns the name of the sequence that is managed by this sequencer.

  Specified by:
    `getSequenceName` in interface `Sequencer`
  Returns:
    The sequence name.

### getSequencerName

    public String getSequencerName()

  Deprecated.
  Returns the name of this sequencer.

  Specified by:
    `getSequencerName` in interface `Sequencer`
  Returns:
    The sequencer name.

### getStepSize

    public long getStepSize()

  Deprecated.
  Returns the step size. The step size determines the difference between the values returned from successive calls to `getNext()`.

  Specified by:
    `getStepSize` in interface `Sequencer`
  Returns:
    The step size.

### setCacheSize

    public void setCacheSize(long cacheSize)

  Deprecated.
  Sets the cache size. The cache size defines how often the sequencer will allocate a block of unique sequence numbers from the database. When the sequencer exhausts its supplied of allocated numbers, it will allocate a new sequence of numbers from the database.

  Specified by:
    `setCacheSize` in interface `Sequencer`
  Parameters:
    `cacheSize` - The cache size.

### setIncrementAmount

    public void setIncrementAmount(long incrementAmount)

  Deprecated. Replaced by setCacheSize

  Sets the increment amount. The increment amount defines how often the sequencer will allocate a block of unique sequence numbers from the database. When the sequencer exhausts its supplied of allocated numbers, it will allocate a new sequence of numbers from the database.

  Specified by:
    `setIncrementAmount` in interface `Sequencer`
  Parameters:
    `incrementAmount` - The increment amount.
  See Also:
    `setCacheSize(long)`

### setSequenceName

    public void setSequenceName(String sequenceName)

  Deprecated.
  Sets the name of the sequence that is managed by this sequencer.

  Specified by:
    `setSequenceName` in interface `Sequencer`
  Parameters:
    `sequenceName` - The new sequence name.

### setSequencerName

    public void setSequencerName(String sequencerName)

  Deprecated.
  Sets the name of this sequencer.

  Specified by:
    `setSequencerName` in interface `Sequencer`
  Parameters:
    `sequencerName` - The new sequencer name.

### setStepSize

    public void setStepSize(long stepSize)

  Deprecated.
  Sets the step size. The step size determines the difference between the values returned from successive calls to `getNext()`.

  Specified by:
    `setStepSize` in interface `Sequencer`
  Parameters:
    `stepSize` - The step size.

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