Class ResultSetJELRowReader

java.lang.Object
gnu.jel.DVMap
uk.ac.starlink.ttools.jel.JELRowReader
uk.ac.starlink.ttools.jel.ResultSetJELRowReader

public class ResultSetJELRowReader extends JELRowReader
JELRowReader for accessing JDBC ResultSet objects. Column indices are 1-based, as for other JDBC methods.
Since:
10 Dec 2007
Author:
Mark Taylor
  • Constructor Details

  • Method Details

    • getColumnIndexByName

      protected int getColumnIndexByName(String name)
      Description copied from class: JELRowReader
      Returns the column index of a column in the row given its name. If name does not refer to any known column, return -1.
      Specified by:
      getColumnIndexByName in class JELRowReader
      Parameters:
      name - column name
      Returns:
      column index, or -1
    • getConstantByName

      protected Constant<?> getConstantByName(String name)
      Description copied from class: JELRowReader
      Returns a constant value for this reader given its name.
      Specified by:
      getConstantByName in class JELRowReader
      Parameters:
      name - constant name
      Returns:
      constant, or null
    • isBlank

      protected boolean isBlank(int icol)
      Description copied from class: JELRowReader
      Indicates whether the value in a given column is null.
      Specified by:
      isBlank in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      true if value at icol is null
    • getColumnClass

      protected Class<?> getColumnClass(int icol)
      Description copied from class: JELRowReader
      Returns the class of values returned by a given column. If no column with the given index exists, null should be returned.
      Specified by:
      getColumnClass in class JELRowReader
      Parameters:
      icol - non-negative column index
      Returns:
      value class, or null for non-existent column
    • getBooleanColumnValue

      protected boolean getBooleanColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a boolean value for a cell of the current row. Will only be called if the relevant column is declared boolean. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getBooleanColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getByteColumnValue

      protected byte getByteColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a byte value for a cell of the current row. Will only be called if the relevant column is declared byte. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getByteColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getCharColumnValue

      protected char getCharColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a char value for a cell of the current row. Will only be called if the relevant column is declared char. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getCharColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getShortColumnValue

      protected short getShortColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a short value for a cell of the current row. Will only be called if the relevant column is declared short. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getShortColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getIntColumnValue

      protected int getIntColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a int value for a cell of the current row. Will only be called if the relevant column is declared int. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getIntColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getLongColumnValue

      protected long getLongColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a long value for a cell of the current row. Will only be called if the relevant column is declared long. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getLongColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getFloatColumnValue

      protected float getFloatColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a float value for a cell of the current row. Will only be called if the relevant column is declared float. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getFloatColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getDoubleColumnValue

      protected double getDoubleColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns a double value for a cell of the current row. Will only be called if the relevant column is declared double. Must call JELRowReader.foundNull() (and return any value) if the result is null.
      Specified by:
      getDoubleColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getObjectColumnValue

      protected Object getObjectColumnValue(int icol)
      Description copied from class: JELRowReader
      Returns an Object value for a cell of the current row.
      Specified by:
      getObjectColumnValue in class JELRowReader
      Parameters:
      icol - column index
      Returns:
      value
    • getSpecialByName

      protected Constant<?> getSpecialByName(String name)
      Description copied from class: JELRowReader
      Returns the a special quantity which corresponds to a given name, or null if it isn't a special. Specials are much like constants but they are checked for earlier.

      The current specials are:

      • "null" returns the null value (this is not built in to the JEL evaluator)
      • "NULL" flags that an attempt has been made to evaluate a primitive with no value, and thus invalidates the rest of the evaluation
      Overrides:
      getSpecialByName in class JELRowReader
      Parameters:
      name - special name
      Returns:
      special, or null