Class StorableFormatId

java.lang.Object
org.apache.derby.iapi.types.DataType
org.apache.derby.impl.store.access.StorableFormatId
All Implemented Interfaces:
Externalizable, Serializable, Comparable, Formatable, Storable, TypedFormat, DataValueDescriptor, Orderable

public class StorableFormatId extends DataType
See Also:
  • Field Details

    • format_id

      private int format_id
    • BASE_MEMORY_USAGE

      private static final int BASE_MEMORY_USAGE
  • Constructor Details

    • StorableFormatId

      public StorableFormatId()
    • StorableFormatId

      public StorableFormatId(int value)
  • Method Details

    • estimateMemoryUsage

      public int estimateMemoryUsage()
      Description copied from interface: DataValueDescriptor
      Estimate the memory usage in bytes of the data value and the overhead of the class.
      Returns:
      the estimated memory usage
    • getValue

      public int getValue()
    • setValue

      public void setValue(int input_value)
      Description copied from class: DataType
      Set the value of this DataValueDescriptor to the given int value At DataType level just throws an error lower classes will override
      Specified by:
      setValue in interface DataValueDescriptor
      Overrides:
      setValue in class DataType
      Parameters:
      input_value - The value to set this DataValueDescriptor to
    • getTypeFormatId

      public int getTypeFormatId()
      Return my format identifier.
      Returns:
      The identifier. (A UUID stuffed in an array of 16 bytes).
      See Also:
    • isNull

      public boolean isNull()
      Description copied from interface: Storable
      Return whether the value is null or not.
      Returns:
      true if the value is null and false otherwise.
    • writeExternal

      public void writeExternal(ObjectOutput out) throws IOException
      Throws:
      IOException
    • readExternal

      public void readExternal(ObjectInput in) throws IOException
      Throws:
      IOException
      See Also:
    • restoreToNull

      public void restoreToNull()
      Description copied from interface: Storable
      Restore this object to its (SQL)null value.
    • getLength

      public int getLength() throws StandardException
      Gets the length of the data value. The meaning of this is implementation-dependent. For string types, it is the number of characters in the string. For numeric types, it is the number of bytes used to store the number. This is the actual length of this value, not the length of the type it was defined as. For example, a VARCHAR value may be shorter than the declared VARCHAR (maximum) length.
      Returns:
      The length of the data value
      Throws:
      StandardException - On error
      See Also:
    • getString

      public String getString() throws StandardException
      Gets the value in the data value descriptor as a String. Throws an exception if the data value is not a string.
      Returns:
      The data value as a String.
      Throws:
      StandardException - Thrown on error
      See Also:
    • getObject

      public Object getObject() throws StandardException
      Gets the value in the data value descriptor as a Java Object. The type of the Object will be the Java object type corresponding to the data value's SQL type. JDBC defines a mapping between Java object types and SQL types - we will allow that to be extended through user type definitions. Throws an exception if the data value is not an object (yeah, right).
      Specified by:
      getObject in interface DataValueDescriptor
      Overrides:
      getObject in class DataType
      Returns:
      The data value as an Object.
      Throws:
      StandardException - Thrown on error
      See Also:
    • cloneValue

      public DataValueDescriptor cloneValue(boolean forceMaterialization)
      Description copied from interface: DataValueDescriptor
      Clone this DataValueDescriptor. Results in a new object that has the same value as this but can be modified independently.

      Even though the objects can be modified independently regardless of the value of forceMaterialization, both the clone and the original may be dependent on the store state if forceMaterialization is set to false. An example is if you need to access the value you just read using cloneValue after the current transaction has ended, or after the source result set has been closed.

      Parameters:
      forceMaterialization - any streams representing the data value will be materialized if true, the data value will be kept as a stream if possible if false
      Returns:
      A clone of the DataValueDescriptor with the same initial value as this.
      See Also:
    • getNewNull

      public DataValueDescriptor getNewNull()
      Get a new null value of the same type as this data value.
      See Also:
    • setValueFromResultSet

      public void setValueFromResultSet(ResultSet resultSet, int colNumber, boolean isNullable) throws StandardException, SQLException
      Set the value based on the value for the specified DataValueDescriptor from the specified ResultSet.
      Parameters:
      resultSet - The specified ResultSet.
      colNumber - The 1-based column # into the resultSet.
      isNullable - Whether or not the column is nullable (No need to call wasNull() if not)
      Throws:
      StandardException - Thrown on error
      SQLException - Error accessing the result set
      See Also:
    • setFrom

      protected void setFrom(DataValueDescriptor theValue) throws StandardException
      Set the value of this DataValueDescriptor from another.
      Overrides:
      setFrom in class DataType
      Parameters:
      theValue - The Date value to set this DataValueDescriptor to
      Throws:
      StandardException
      See Also:
    • getTypeName

      public String getTypeName()
      Get the SQL name of the datatype
      Returns:
      The SQL name of the datatype
      See Also:
    • compare

      public int compare(DataValueDescriptor other) throws StandardException
      Compare this Orderable with a given Orderable for the purpose of index positioning. This method treats nulls as ordered values - that is, it treats SQL null as equal to null and less than all other values.
      Parameters:
      other - The Orderable to compare this one to.
      Returns:
      <0 - this Orderable is less than other. 0 - this Orderable equals other. >0 - this Orderable is greater than other. The code should not explicitly look for -1, or 1.
      Throws:
      StandardException - Thrown on error
      See Also: