AbstractStarTable (Starlink-UK API)

java.lang.Object
- uk.ac.starlink.table.AbstractStarTable

All Implemented Interfaces:

Closeable, AutoCloseable, StarTable

Direct Known Subclasses:

AsciiTableStarTable, AttractorStarTable, BintableStarTable, CalcStarTable, CdfStarTable, ColFitsStarTable, EcsvStarTable, FeatherStarTable, GbinStarTable, JDBCStarTable, JoinStarTable, MetadataStarTable, ParquetStarTable, Pds4StarTable, RandomStarTable, SequentialResultSetStarTable, StreamStarTable, UploadConeTable, VOStarTable
```
public abstract class AbstractStarTable
extends Object
implements StarTable
```
Abstract base class providing an implementation of the generic and straightforward parts of the StarTable interface. This implementation assumes that random access is not available; subclasses which provide random access should override the isRandom, getCell and perhaps getRow methods.

Author:

Mark Taylor (Starlink)

Constructor Summary

Constructors
Constructor and Description

AbstractStarTable()

Constructors
Constructor and Description
`AbstractStarTable()`

Method Summary

All Methods Static Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method and Description
`static int`	`checkedLongToInt(long lval)` Convenience method to get an `int` value from a `long`.
`void`	`close()` The `AbstractStarTable` implementation of this method does nothing.
`Object`	`getCell(long irow, int icol)` The `AbstractStarTable` implementation of this method throws an `UnsupportedOperationException`, since unless otherwise provided there is no random access.
`List<ValueInfo>`	`getColumnAuxDataInfos()` Goes through the table columns (`ColumnInfo` objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name.
`abstract int`	`getColumnCount()` Returns the number of columns in this table.
`abstract ColumnInfo`	`getColumnInfo(int icol)` Returns the object describing the data in a given column.
`String`	`getName()` Returns the name of this table, if it has one.
`List<DescribedValue>`	`getParameters()` Returns a list of table parameters, that is metadata items which pertain to the entire table.
`Object[]`	`getRow(long irow)` The `AbstractStarTable` implementation of this method constructs a row by repeated invocation of `getCell(long, int)`.
`RowAccess`	`getRowAccess()` Returns an object which can provide random access to this table's data, if random access is implemented.
`abstract long`	`getRowCount()` Returns the number of rows in this table, if known.
`abstract RowSequence`	`getRowSequence()` Returns an object which can iterate over all the rows in the table sequentially.
`RowSplittable`	`getRowSplittable()` Returns a default splittable which relies on table random access if available, or otherwise provides only sequential access (no splits).
`URL`	`getURL()` Returns the URL of this table, if it has one.
`boolean`	`isRandom()` The `AbstractStarTable` implementation of this method returns `false`.
`void`	`setName(String name)` Sets the name for this table.
`void`	`setParameters(List<DescribedValue> parameters)` Sets the list of table parameters, that is items which pertain to the entire table.
`void`	`setURL(URL url)` Sets the URL for this table.

Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from interface uk.ac.starlink.table.StarTable
getParameterByName, setParameter

- Constructor Detail
  - AbstractStarTable
```
public AbstractStarTable()
```
- Method Detail
  - getColumnAuxDataInfos
```
public List<ValueInfo> getColumnAuxDataInfos()
```
    Goes through the table columns (ColumnInfo objects) and picks out all the AuxData items which exist, generalising where necessary and returning a union of them in alphabetical order by name. Subclasses should override this if they can do better, for instance providing an order for the keys.
    
    Specified by:
    
    getColumnAuxDataInfos in interface StarTable
    
    Returns:
    
    a list of all the auxiliary metadata ValueInfo items which in fact crop up in column metadata
    
    See Also:
    
    DefaultValueInfo.getAuxData()
  - getParameters
```
public 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
  - setParameters
```
public void setParameters(List<DescribedValue> parameters)
```
    Sets the list of table parameters, that is items which pertain to the entire table. Each element of the provided list parameters should be a DescribedValue object.
    
    Parameters:
    
    parameters - a List of DescribedValues pertaining to this table
  - getName
```
public 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(String name)
```
    Sets the name for this table.
    
    Specified by:
    
    setName in interface StarTable
    
    Parameters:
    
    name - the table name - may be null
  - getURL
```
public URL getURL()
```
    Description copied from interface: StarTable
    
    Returns the URL of this table, if it has one. A non-null return from this method indicates that this table is in some sense persistent.
    
    Specified by:
    
    getURL in interface StarTable
    
    Returns:
    
    the URL of this table, or null if none is known
  - setURL
```
public void setURL(URL url)
```
    Sets the URL for this table.
    
    Specified by:
    
    setURL in interface StarTable
    
    Parameters:
    
    url - the URL where this table lives - may be null
  - checkedLongToInt
```
public static int checkedLongToInt(long lval)
```
    Convenience method to get an int value from a long. Invokes Tables.checkedLongToInt(long).
  - isRandom
```
public boolean isRandom()
```
    The AbstractStarTable implementation of this method returns false.
    
    Specified by:
    
    isRandom in interface StarTable
    
    Returns:
    
    true if table random access methods are available
  - getRowAccess
```
public RowAccess getRowAccess()
                       throws 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:
    
    IOException - if there is an error setting up access
  - getRowSplittable
```
public RowSplittable getRowSplittable()
                               throws IOException
```
    Returns a default splittable which relies on table random access if available, or otherwise provides only sequential access (no splits).
    It is often possible to provide a better implementation than this.
    
    Specified by:
    
    getRowSplittable in interface StarTable
    
    Returns:
    
    Tables.getDefaultRowSplittable(this)
    
    Throws:
    
    IOException
    
    See Also:
    
    RowRunner
  - getCell
```
public Object getCell(long irow,
                      int icol)
               throws IOException
```
    The AbstractStarTable implementation of this method throws an UnsupportedOperationException, since unless otherwise provided there is no random access.
    
    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:
    
    IOException - if there is an error reading the data
  - getRow
```
public Object[] getRow(long irow)
                throws IOException
```
    The AbstractStarTable implementation of this method constructs a row by repeated invocation of getCell(long, int).
    
    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:
    
    IOException - if there is an error reading the data
  - close
```
public void close()
           throws IOException
```
    The AbstractStarTable implementation of this method does nothing.
    
    Specified by:
    
    close in interface Closeable
    
    Specified by:
    
    close in interface AutoCloseable
    
    Specified by:
    
    close in interface StarTable
    
    Throws:
    
    IOException
  - getColumnInfo
```
public abstract 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
  - getColumnCount
```
public abstract 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 abstract 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
  - getRowSequence
```
public abstract RowSequence getRowSequence()
                                    throws 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:
    
    IOException - if there is an error providing access

Class AbstractStarTable

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface uk.ac.starlink.table.StarTable

Constructor Detail

AbstractStarTable

Method Detail

getColumnAuxDataInfos

getParameters

setParameters

getName

setName

getURL

setURL

checkedLongToInt

isRandom

getRowAccess

getRowSplittable

getCell

getRow

close

getColumnInfo

getColumnCount

getRowCount

getRowSequence