Package uk.ac.starlink.topcat

Class TopcatJELRowReader

java.lang.Object
gnu.jel.DVMap
uk.ac.starlink.ttools.jel.JELRowReader
uk.ac.starlink.ttools.jel.StarTableJELRowReader
uk.ac.starlink.ttools.jel.RandomJELRowReader
uk.ac.starlink.topcat.TopcatJELRowReader
public abstract class TopcatJELRowReader extends uk.ac.starlink.ttools.jel.RandomJELRowReader
Random JELRowReader with which recognises some expressions in addition to those of the superclass.
Row Subset _ID identifiers:
The character '_' followed by the 1-based index of a defined row subset returns true iff the current row is part of the subset.
Row Subset names:
The name of a subset (case-insensitive) returns true iff the current row is part of the named subset.
Apparent table index:
The tokens "$index0" or "$00" (case insensitive) are evaluated as the index of the current row in the apparent table; this differs from $index/$0 if a non-default sort order or current subset is in force.
Apparent table row count:
The token "$nrow0" is the number of rows in the apparent table; this differs from $nrow if a non-default current subset is in force.
Apparent table column count:
The token "$ncol0 is the number of columns in the apparent table; this differs from $ncol if some columns are hidden.
Since:
8 Feb 2005
Author:
Mark Taylor (Starlink)

  • Field Summary

    Fields
    Modifier and Type
    Field
    Description
    static final char
    SUBSET_ID_CHAR
    Prefix identifying a unique subset identifier.

    Fields inherited from class uk.ac.starlink.ttools.jel.StarTableJELRowReader

    PARAM_PREFIX, UCD_PREFIX, UTYPE_PREFIX

    Fields inherited from class uk.ac.starlink.ttools.jel.JELRowReader

    COLUMN_ID_CHAR, NULL_QUERY_PREFIX, OBJECT_PREFIX

  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    TopcatJELRowReader(TopcatModel tcModel)
    Constructs a new row reader for a TopcatModel.

  • Method Summary

    Modifier and Type
    Method
    Description
    static TopcatJELRowReader
    createAccessReader(TopcatModel tcModel)
    Returns a reader that uses a RowAccess object from the TopcatModel's data model.
    static TopcatJELRowReader
    createConcurrentReader(TopcatModel tcModel)
    Returns a reader that uses the threadsafe random access methods of the TopcatModel's data model.
    protected uk.ac.starlink.ttools.jel.Constant<?>
    createDescribedValueConstant(uk.ac.starlink.table.DescribedValue dval)
    Returns a constant which is evaluated at runtime.
    static TopcatJELRowReader
    createDummyReader(TopcatModel tcModel)
    Returns a reader that doesn't do any actual data access.
    abstract boolean
    evaluateBooleanAtRow(gnu.jel.CompiledExpression compEx, long lrow)
    Evaluates a given compiled expression of boolean return type at a given row.
    boolean
    getBooleanProperty(short isub)
    Returns the actual subset value for the current row and a given column.
    protected uk.ac.starlink.ttools.jel.Constant<?>
    getSpecialByName(String name)
     
    TopcatModel
    getTopcatModel()
    Returns the topcat model on which this row reader is based.
    int[]
    getTranslatedSubsetIds()
    Returns a set (no duplicated elements) of the subset IDs for which this RowReader has been asked to provide translation values.
    String
    getTypeName(String name)
    Overrides superclass implementation to recognise row subsets by name or _ID.
    Object
    translate(String name)
    Overrides superclass implementation to recognise subsets as well as the other special objects.

    Methods inherited from class uk.ac.starlink.ttools.jel.RandomJELRowReader

    createAccessReader, createAccessReader, createConcurrentReader, evaluateAtRow

    Methods inherited from class uk.ac.starlink.ttools.jel.StarTableJELRowReader

    getBooleanColumnValue, getByteColumnValue, getCell, getCharColumnValue, getColumnClass, getColumnIndexByName, getConstantByName, getCurrentRow, getDescribedValueByName, getDoubleColumnValue, getFloatColumnValue, getIntColumnValue, getLongColumnValue, getObjectColumnValue, getShortColumnValue, getTable, getUcdRegex, getUtypeRegex, isBlank, requiresRowIndex, valueDouble, valueInt, valueLong, valueObject, valueString

    Methods inherited from class uk.ac.starlink.ttools.jel.JELRowReader

    evaluate, evaluateBoolean, evaluateDouble, foundNull, getBooleanArrayProperty, getBooleanProperty, getBooleanProperty, getBooleanValue, getByteArrayProperty, getByteProperty, getByteValue, getCharArrayProperty, getCharProperty, getCharValue, getColumnIndex, getDateArrayProperty, getDoubleArrayProperty, getDoubleProperty, getDoubleValue, getFloatArrayProperty, getFloatProperty, getFloatValue, getIntArrayProperty, getIntProperty, getIntValue, getLongArrayProperty, getLongProperty, getLongValue, getNumberProperty, getObjectArrayProperty, getObjectProperty, getShortArrayProperty, getShortProperty, getShortValue, getStringArrayProperty, getStringProperty, getTranslatedColumns, getTranslatedConstants, setFailOnNull, stripPrefix

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

  • Field Details

    • SUBSET_ID_CHAR

      public static final char SUBSET_ID_CHAR
      Prefix identifying a unique subset identifier.
      See Also:

  • Constructor Details

    • TopcatJELRowReader

      protected TopcatJELRowReader(TopcatModel tcModel)
      Constructs a new row reader for a TopcatModel.
      Parameters:
      tcModel - topcat model

  • Method Details

    • getTopcatModel

      public TopcatModel getTopcatModel()
      Returns the topcat model on which this row reader is based.
      Returns:
      topcat model

    • evaluateBooleanAtRow

      public abstract boolean evaluateBooleanAtRow(gnu.jel.CompiledExpression compEx, long lrow) throws Throwable
      Evaluates a given compiled expression of boolean return type at a given row.
      Parameters:
      compEx - compiled boolean expression
      lrow - row at which to evaluate
      Returns:
      expression value
      Throws:
      Throwable

    • getTypeName

      public String getTypeName(String name)
      Overrides superclass implementation to recognise row subsets by name or _ID.
      Overrides:
      getTypeName in class uk.ac.starlink.ttools.jel.JELRowReader
      Parameters:
      name - the variable name
      Returns:
      corresponding method name fragment
      See Also:
      • "JEL manual"

    • translate

      public Object translate(String name)
      Overrides superclass implementation to recognise subsets as well as the other special objects. The additional return type is:
      • a Short (the subset index) if the column specification appears to reference a known row subset
      Overrides:
      translate in class uk.ac.starlink.ttools.jel.JELRowReader
      Parameters:
      name - the name of the variable-like object to evaluate
      Returns:
      a numeric object corresponding to an object which we know how to evaluate
      See Also:
      • "JEL manual"

    • getTranslatedSubsetIds

      public int[] getTranslatedSubsetIds()
      Returns a set (no duplicated elements) of the subset IDs for which this RowReader has been asked to provide translation values. In practice that means the ID (in the sense of the OptionsListModel returned by TopcatModel.getSubsets) of every RowSubset which has been directly referenced in a JEL expression which this RowReader has been used to compile.
      Returns:
      list of distinct subset IDs which this row reader has had to reference in compiling JEL expressions

    • getBooleanProperty

      public boolean getBooleanProperty(short isub)
      Returns the actual subset value for the current row and a given column.
      Parameters:
      isub - index of the subset to evaluate at the current row
      Returns:
      result of the isIncluded method of the RowSubset indicated at the current row

    • getSpecialByName

      protected uk.ac.starlink.ttools.jel.Constant<?> getSpecialByName(String name)
      Overrides:
      getSpecialByName in class uk.ac.starlink.ttools.jel.StarTableJELRowReader

    • createDescribedValueConstant

      protected uk.ac.starlink.ttools.jel.Constant<?> createDescribedValueConstant(uk.ac.starlink.table.DescribedValue dval)
      Returns a constant which is evaluated at runtime. This is more appropriate than the inherited (evaluate at call time) behaviour, since within TOPCAT the constant's value may change as a result of user intervention during the lifetime of the returned object.
      Overrides:
      createDescribedValueConstant in class uk.ac.starlink.ttools.jel.StarTableJELRowReader

    • createConcurrentReader

      public static TopcatJELRowReader createConcurrentReader(TopcatModel tcModel)
      Returns a reader that uses the threadsafe random access methods of the TopcatModel's data model.
      Parameters:
      tcModel - topcat model
      Returns:
      threadsafe row reader

    • createAccessReader

      public static TopcatJELRowReader createAccessReader(TopcatModel tcModel)
      Returns a reader that uses a RowAccess object from the TopcatModel's data model.
      Parameters:
      tcModel - topcat model
      Returns:
      row reader suitable for use only within a single thread

    • createDummyReader

      public static TopcatJELRowReader createDummyReader(TopcatModel tcModel)
      Returns a reader that doesn't do any actual data access. Suitable for testing compilation success etc.
      Parameters:
      tcModel - topcat model
      Returns:
      row reader that throws UnsupportedOperationException for data access methods