java.lang.Object
- org.apache.cayenne.map.Relationship

All Implemented Interfaces:

Serializable, CayenneMapEntry, XMLSerializable

Direct Known Subclasses:

DbRelationship, ObjRelationship
```
public abstract class Relationship
extends Object
implements CayenneMapEntry, XMLSerializable, Serializable
```
Defines a relationship between two entities. In a DataMap graph relationships represent "arcs" connecting entity "nodes". Relationships are directional, i.e. they have a notion of source and target entity. This makes DataMap a "digraph".

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`protected String`	`name`
`protected boolean`	`runtime`	A flag that specifies whether a Relationship was mapped by the user or added dynamically by Cayenne runtime.
`protected Entity`	`sourceEntity`
`protected String`	`targetEntityName`
`protected boolean`	`toMany`

Constructor Summary

Constructors
Constructor Description

Relationship()
Creates an unnamed relationship.

Relationship(String name)
Creates a named relationship.

Method Summary

All Methods Instance Methods Abstract Methods Concrete Methods
Modifier and Type	Method	Description
`String`	`getName()`	Returns the name property of this object.
`Object`	`getParent()`	Returns the parent map.
`abstract Relationship`	`getReverseRelationship()`	Returns a "complimentary" relationship going in the opposite direction.
`Entity`	`getSourceEntity()`	Returns relationship source entity.
`abstract Entity`	`getTargetEntity()`	Returns a target entity of the relationship.
`String`	`getTargetEntityName()`	Returns the name of a target entity.
`abstract boolean`	`isMandatory()`	Returns if relationship is mandatory
`boolean`	`isRuntime()`
`boolean`	`isToMany()`	Returns a boolean value that determines relationship multiplicity.
`void`	`setName(String name)`
`void`	`setParent(Object parent)`	Stores the parent map.
`void`	`setRuntime(boolean synthetic)`
`void`	`setSourceEntity(Entity sourceEntity)`	Sets relationship source entity.
`void`	`setTargetEntityName(String targetEntityName)`	Sets the name of relationship target entity.
`void`	`setTargetEntityName(Entity targetEntity)`	Sets relationship target entity.
`String`	`toString()`	Overrides Object.toString() to return informative description.

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

Methods inherited from interface org.apache.cayenne.util.XMLSerializable
encodeAsXML

- Field Detail
  - name
```
protected String name
```
  - sourceEntity
```
protected Entity sourceEntity
```
  - targetEntityName
```
protected String targetEntityName
```
  - toMany
```
protected boolean toMany
```
  - runtime
```
protected boolean runtime
```
    A flag that specifies whether a Relationship was mapped by the user or added dynamically by Cayenne runtime.
    
    Since:
    
    3.0
- Constructor Detail
  - Relationship
```
public Relationship()
```
    Creates an unnamed relationship.
  - Relationship
```
public Relationship(String name)
```
    Creates a named relationship.
- Method Detail
  - getName
```
public String getName()
```
    Description copied from interface: CayenneMapEntry
    
    Returns the name property of this object.
    
    Specified by:
    
    getName in interface CayenneMapEntry
    
    Returns:
    
    name of this entry.
  - setName
```
public void setName(String name)
```
  - getSourceEntity
```
public Entity getSourceEntity()
```
    Returns relationship source entity.
  - setSourceEntity
```
public void setSourceEntity(Entity sourceEntity)
```
    Sets relationship source entity.
  - getTargetEntity
```
public abstract Entity getTargetEntity()
```
    Returns a target entity of the relationship.
  - setTargetEntityName
```
public void setTargetEntityName(Entity targetEntity)
```
    Sets relationship target entity. Internally calls setTargetEntityName.
  - getTargetEntityName
```
public String getTargetEntityName()
```
    Returns the name of a target entity.
  - setTargetEntityName
```
public void setTargetEntityName(String targetEntityName)
```
    Sets the name of relationship target entity.
  - isToMany
```
public boolean isToMany()
```
    Returns a boolean value that determines relationship multiplicity. This defines semantics of the connection between two nodes described by the source and target entities. E.g. to-many relationship between two Persistent object classes means that a source object would have a collection of target objects. This is a read-only property.
  - getParent
```
public Object getParent()
```
    Description copied from interface: CayenneMapEntry
    
    Returns the parent map.
    
    Specified by:
    
    getParent in interface CayenneMapEntry
  - setParent
```
public void setParent(Object parent)
```
    Description copied from interface: CayenneMapEntry
    
    Stores the parent map.
    
    Specified by:
    
    setParent in interface CayenneMapEntry
  - toString
```
public String toString()
```
    Overrides Object.toString() to return informative description.
    
    Overrides:
    
    toString in class Object
  - isRuntime
```
public boolean isRuntime()
```
    Since:
    
    3.0
  - setRuntime
```
public void setRuntime(boolean synthetic)
```
    Since:
    
    3.0
  - getReverseRelationship
```
public abstract Relationship getReverseRelationship()
```
    Returns a "complimentary" relationship going in the opposite direction. Returns null if no such relationship is found.
    
    Since:
    
    3.1
  - isMandatory
```
public abstract boolean isMandatory()
```
    Returns if relationship is mandatory
    
    Since:
    
    3.1

Constructor	Description
`Relationship()`	Creates an unnamed relationship.
`Relationship(String name)`	Creates a named relationship.

Class Relationship

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from interface org.apache.cayenne.util.XMLSerializable

Field Detail

name

sourceEntity

targetEntityName

toMany

runtime

Constructor Detail

Relationship

Relationship

Method Detail

getName

setName

getSourceEntity

setSourceEntity

getTargetEntity

setTargetEntityName

getTargetEntityName

setTargetEntityName

isToMany

getParent

setParent

toString

isRuntime

setRuntime

getReverseRelationship

isMandatory