RowLink (Starjava Table API)

java.lang.Object
- uk.ac.starlink.table.join.RowLink

All Implemented Interfaces:

java.lang.Comparable

Direct Known Subclasses:

PairsRowLink, RowLink2
```
public class RowLink
extends java.lang.Object
implements java.lang.Comparable
```
Represents an ordered set of RowRefs which are considered in some way linked to each other. Although it doesn't implement the SortedSet interface (being immutable this wouldn't gain you much) its spirit is that of a sorted set - its equals and hashCode methods are implemented such that two RowLinks which contain equivalent groups of RowRef objects are considered the same. This makes RowLink instances suitable for use as keys in hashes that should not contain duplicate entries for duplicate links. The getRef method returns RowRefs in their natural order.

Author:

Mark Taylor (Starlink)

Constructor Summary

Constructors
Constructor and Description
`RowLink(java.util.Collection rows)` Constructs a new RowLink from a Collection of `RowRef` objects.
`RowLink(RowRef row)` Convenience constructor to construct a singleton RowLink.
`RowLink(RowRef[] rows)` Constructs a new RowLink from an array of `RowRef` objects.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`int`	`compareTo(java.lang.Object o)` Comparison order compares first table (if present in both objects) first, etc.
`boolean`	`equals(java.lang.Object o)` Assesses equality.
`RowRef`	`getRef(int i)` Returns the `i`^th row ref in this link.
`int`	`hashCode()` Returns a hash code which is consistent with the `equals` method.
`int`	`size()` Returns the number of rows linked by this object.
`java.lang.String`	`toString()`

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

- Constructor Detail
  - RowLink
```
public RowLink(java.util.Collection rows)
```
    Constructs a new RowLink from a Collection of RowRef objects. An unchecked exception will be thrown if rows contains some elements which are not instances of RowRef.
    
    Parameters:
    
    rows - collection of RowRef objects
  - RowLink
```
public RowLink(RowRef[] rows)
```
    Constructs a new RowLink from an array of RowRef objects.
    
    Parameters:
    
    rows - array of row references
  - RowLink
```
public RowLink(RowRef row)
```
    Convenience constructor to construct a singleton RowLink.
    
    Parameters:
    
    row - sole row
- Method Detail
  - size
```
public int size()
```
    Returns the number of rows linked by this object.
    
    Returns:
    
    number of RowRefs
  - getRef
```
public RowRef getRef(int i)
```
    Returns the i^th row ref in this link.
    
    Parameters:
    
    i - index
    
    Returns:
    
    RowRef at i
  - equals
```
public boolean equals(java.lang.Object o)
```
    Assesses equality. Two RowLink objects are equal if they contain equivalent sets of RowRefs.
    
    Overrides:
    
    equals in class java.lang.Object
  - hashCode
```
public int hashCode()
```
    Returns a hash code which is consistent with the equals method. Since RowLinks are immutable, this is only calculated once, for efficiency.
    
    Overrides:
    
    hashCode in class java.lang.Object
  - compareTo
```
public int compareTo(java.lang.Object o)
```
    Comparison order compares first table (if present in both objects) first, etc.
    
    Specified by:
    
    compareTo in interface java.lang.Comparable
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class RowLink

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

RowLink

RowLink

RowLink

Method Detail

size

getRef

equals

hashCode

compareTo

toString