Package uk.ac.starlink.table

Class WrapperStarTable

    • Constructor Summary

      Constructors 
      Constructor Description
      WrapperStarTable​(StarTable baseTable)
      Constructs a new WrapperStarTable from a given base table.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods 
      Modifier and Type Method Description
      static int checkedLongToInt​(long lval)
      Convenience method to get an int value from a long.
      void close()
      Relinquishes any resources associated with this table.
      StarTable getBaseTable()
      Returns the base table underlying this wrapper table.
      java.lang.Object getCell​(long irow, int icol)
      Returns the contents of a given table cell.
      java.util.List<ValueInfo> getColumnAuxDataInfos()
      Returns an ordered list of ValueInfo objects representing the auxiliary metadata returned by getColumnInfo(int).getAuxData() calls.
      int getColumnCount()
      Returns the number of columns in this table.
      ColumnInfo getColumnInfo​(int icol)
      Returns the object describing the data in a given column.
      java.lang.String getName()
      Returns the name of this table, if it has one.
      DescribedValue getParameterByName​(java.lang.String parname)
      Returns a parameter (table-wide metadata item) of this table located by its name.
      java.util.List<DescribedValue> getParameters()
      Returns a list of table parameters, that is metadata items which pertain to the entire table.
      java.lang.Object[] getRow​(long irow)
      Returns the contents of a given table row.
      RowAccess getRowAccess()
      Returns an object which can provide random access to this table's data, if random access is implemented.
      long getRowCount()
      Returns the number of rows in this table, if known.
      RowSequence getRowSequence()
      Returns an object which can iterate over all the rows in the table sequentially.
      RowSplittable getRowSplittable()
      Returns an object which can iterate over all the rows in the table, but which may also be requested to split recursively for potentially parallel processing.
      java.net.URL getURL()
      Initially returns null to indicate that this table itself is not persistent.
      boolean isRandom()
      Indicates whether random access is provided by this table.
      void setName​(java.lang.String name)
      Sets the name of this table.
      void setParameter​(DescribedValue dval)
      Adds the given DescribedValue to the list of parameter metadata objects associated with this table.
      void setURL​(java.net.URL url)
      Sets the URL of this table.
      java.lang.String toString()
      Returns an indication of the wrapper structure of this table.

      • Methods inherited from class java.lang.Object

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

    • Field Detail

    • Constructor Detail

      • WrapperStarTable

        public WrapperStarTable​(StarTable baseTable)
        Constructs a new WrapperStarTable from a given base table.
        Parameters:
        baseTable - the table to which methods invoked upon the new wrapper table will be forwarded

    • Method Detail

      • getBaseTable

        public StarTable getBaseTable()
        Returns the base table underlying this wrapper table.
        Returns:
        the table to which methods invoked upon this wrappter table are forwarded

      • getColumnCount

        public int getColumnCount()
        Description copied from interface: StarTable
        Returns the number of columns in this table.
        Specified by:
        getColumnCount in interface StarTable
        Returns:
        the number of columns

      • getRowCount

        public long getRowCount()
        Description copied from interface: StarTable
        Returns the number of rows in this table, if known. If the number of rows cannot be (easily) determined, a value of -1 will be returned.
        Specified by:
        getRowCount in interface StarTable
        Returns:
        the number of rows, or -1

      • getURL

        public java.net.URL getURL()
        Initially returns null to indicate that this table itself is not persistent.
        Specified by:
        getURL in interface StarTable
        Returns:
        the URL of this table, or null if none is known

      • setURL

        public void setURL​(java.net.URL url)
        Description copied from interface: StarTable
        Sets the URL of this table. It ought to be possible in principle to reconstruct this table by reading the resource at url. If called, the supplied url should provide the return value for subsequent calls of StarTable.getURL().
        Specified by:
        setURL in interface StarTable
        Parameters:
        url - table URL

      • getName

        public java.lang.String getName()
        Description copied from interface: StarTable
        Returns the name of this table, if it has one. The meaning of the name is not defined, but it will typically be a short string of text indicating the identity of this table.
        Specified by:
        getName in interface StarTable
        Returns:
        a name for this table, or null if no suitable one exists

      • setName

        public void setName​(java.lang.String name)
        Description copied from interface: StarTable
        Sets the name of this table. If called, the supplied name should provide the return value for subsequent calls of StarTable.getName().
        Specified by:
        setName in interface StarTable
        Parameters:
        name - table name

      • getParameters

        public java.util.List<DescribedValue> getParameters()
        Description copied from interface: StarTable
        Returns a list of table parameters, that is metadata items which pertain to the entire table.
        Specified by:
        getParameters in interface StarTable
        Returns:
        a List of DescribedValue objects constituting table-wide metadata not covered elsewhere in this interface

      • getParameterByName

        public DescribedValue getParameterByName​(java.lang.String parname)
        Description copied from interface: StarTable
        Returns a parameter (table-wide metadata item) of this table located by its name. If more than one parameter with the given name exists, an arbitrary one will be returned. If no parameter with the given name exists, null will be returned.
        Specified by:
        getParameterByName in interface StarTable
        Parameters:
        parname - the name of the table parameter required

      • setParameter

        public void setParameter​(DescribedValue dval)
        Description copied from interface: StarTable
        Adds the given DescribedValue to the list of parameter metadata objects associated with this table. If an item in the parameter list with the same name as the supplied value already exists, it is removed from the list.
        Specified by:
        setParameter in interface StarTable
        Parameters:
        dval - the new parameter datum to add

      • getColumnInfo

        public ColumnInfo getColumnInfo​(int icol)
        Description copied from interface: StarTable
        Returns the object describing the data in a given column.
        Specified by:
        getColumnInfo in interface StarTable
        Parameters:
        icol - the column for which header information is required
        Returns:
        a ValueInfo object for column icol

      • getColumnAuxDataInfos

        public java.util.List<ValueInfo> getColumnAuxDataInfos()
        Description copied from interface: StarTable
        Returns an ordered list of ValueInfo objects representing the auxiliary metadata returned by getColumnInfo(int).getAuxData() calls. The idea is that the resulting list can be used to find out the kind of per-column metadata which can be expected to be found in some or all columns of this table. Each item in the returned list should have a unique name, and other characteristics which are applicable to auxData items which may be returned from any of the columns in this table.

        The order of the list may indicate some sort of natural ordering of these keys. The returned list is not guaranteed to be complete; it is legal to return an empty list if nothing is known about auxiliary metadata. The list ought not to contain duplicate elements.

        Specified by:
        getColumnAuxDataInfos in interface StarTable
        Returns:
        an unmodifiable ordered set of known metadata keys
        See Also:
        DefaultValueInfo.getAuxData()

      • getRowSequence

        public RowSequence getRowSequence()
                           throws java.io.IOException
        Description copied from interface: StarTable
        Returns an object which can iterate over all the rows in the table sequentially. Each such returned object is safe for use within a single thread, but not in general from multiple threads concurrently.
        Specified by:
        getRowSequence in interface StarTable
        Returns:
        new RowSequence
        Throws:
        java.io.IOException - if there is an error providing access

      • getRowAccess

        public RowAccess getRowAccess()
                       throws java.io.IOException
        Description copied from interface: StarTable
        Returns an object which can provide random access to this table's data, if random access is implemented. Each such returned object is safe for use within a single thread, but not in general from multiple threads concurrently.
        Specified by:
        getRowAccess in interface StarTable
        Returns:
        new RowAccess
        Throws:
        java.io.IOException - if there is an error setting up access

      • getRowSplittable

        public RowSplittable getRowSplittable()
                               throws java.io.IOException
        Description copied from interface: StarTable
        Returns an object which can iterate over all the rows in the table, but which may also be requested to split recursively for potentially parallel processing.

        The return value must be non-null, and may provide splitting arrangements specially appropriate for the implementation. If this table 'wraps' an upstream table, it is usually best to base the implementation on calls to the the upstream getRowSplittable method, so that upstream policy about how to divide up the table is respected. However, implementations without special requirements may return Tables.getDefaultRowSplittable(this).

        Specified by:
        getRowSplittable in interface StarTable
        Returns:
        new RowSplittable
        Throws:
        java.io.IOException
        See Also:
        RowRunner

      • getCell

        public java.lang.Object getCell​(long irow,
                                int icol)
                         throws java.io.IOException
        Description copied from interface: StarTable
        Returns the contents of a given table cell. The class of the returned object should be the same as, or a subclass of, the class returned by getColumnInfo(icol).getContentClass().

        This method is safe for concurrent use from multiple threads, but in general it is recommended to use a RowAccess instead.

        Specified by:
        getCell in interface StarTable
        Parameters:
        irow - the index of the cell's row
        icol - the index of the cell's column
        Returns:
        the contents of this cell
        Throws:
        java.io.IOException - if there is an error reading the data

      • getRow

        public java.lang.Object[] getRow​(long irow)
                          throws java.io.IOException
        Description copied from interface: StarTable
        Returns the contents of a given table row. The returned value is equivalent to an array formed of all the objects returned by getCell(irow,icol) for all the columns icol in sequence.

        This method is safe for concurrent use from multiple threads, but in general it is recommended to use a RowAccess instead.

        Specified by:
        getRow in interface StarTable
        Parameters:
        irow - the index of the row to retrieve
        Returns:
        an array of the objects in each cell in row irow
        Throws:
        java.io.IOException - if there is an error reading the data

      • close

        public void close()
           throws java.io.IOException
        Description copied from interface: StarTable
        Relinquishes any resources associated with this table. This may do nothing, and calling it is often not required, but it provides an opportunity to force release of file descriptors or other resources that are not well handled by garbage collection if the table itself holds them. It is not intended for release of heap-based resources, for which garbage collection already provides adequate management.

        Following a call to this method, any attempt to use this table or objects such as RowSequences obtained from it will result in undefined behaviour.

        Specified by:
        close in interface java.lang.AutoCloseable
        Specified by:
        close in interface java.io.Closeable
        Specified by:
        close in interface StarTable
        Throws:
        java.io.IOException

      • checkedLongToInt

        public static int checkedLongToInt​(long lval)
        Convenience method to get an int value from a long. Invokes Tables.checkedLongToInt(long).

      • toString

        public java.lang.String toString()
        Returns an indication of the wrapper structure of this table.
        Overrides:
        toString in class java.lang.Object
        Returns:
        string representation