Module org.eclipse.persistence.core
Package org.eclipse.persistence.internal.helper

Class LOBValueWriter

java.lang.Object
org.eclipse.persistence.internal.helper.LOBValueWriter
public class LOBValueWriter extends Object
INTERNAL:

Purpose:LOBValueWriter is used to write a large size of object into an Oracle CLOB/BLOB column through Oracle LOB Locator. It's a work-around object for the well-known 4k write limits on an Oracle thin driver.

Responsibilities:

  • Build the Oracle empty lob method call string for the insert call.
  • Build the minimal SELECT call to retrieve the locator.
  • Write the lob value through the locator.
  • Resolve the multiple table INSERT/SELECT orders.
  • Resolve the nested unit of work commit issue.
Since:
TopLink/Java 5.0. July 2002.

  • Constructor Details

    • LOBValueWriter

      public LOBValueWriter(Accessor accessor)
      This is the default constructor for the class. Bug 2804663 - Each DatabaseAccessor will now hold on to its own instance of this class, hence a singleton pattern is not applicable.

  • Method Details

    • buildAndExecuteCall

      protected void buildAndExecuteCall(DatabaseCall dbCall, AbstractSession session)

    • fetchLocatorAndWriteValue

      public void fetchLocatorAndWriteValue(DatabaseCall dbCall, Object resultSet) throws SQLException
      Fetch the locator(s) from the result set and write LOB value to the table
      Throws:
      SQLException

    • addCall

      public void addCall(Call call)
      Add original (insert or update) call to the collection

    • buildAndExecuteSelectCalls

      public void buildAndExecuteSelectCalls(AbstractSession session)
      Build and execute the deferred select calls.