NetworkExplorer (Oracle Spatial and Graph Java API Reference)

java.lang.Object
- oracle.spatial.network.lod.NetworkExplorer

```
public class NetworkExplorer
extends java.lang.Object
```
This class provides methods to navigate a network. The network may contain dynamic network update information superimposed on the static network information.
The following summarizes the basic steps in network navigation starting from a node:
1. From the input node ID, get the network node object (LogicalNetNode) by calling
```
       networkExplorer.getNetNode(nodeId)
     
```
The returned LogicalNetNode object contains reference to its adjacent network links, which in turn contains references to the next nodes, and so on.
2. From the returned LogicalNetNode object, get the next node IDs or adjacent network link objects (LogicalNetLink), e.g.,
```
        netNode.getNextNodeIds(...), or
        netNode.getOutLinks(...)
     
```
3. From the returned LogicalNetLink objects, get the adjacent network node objects (LogicalNetNode), e.g.,
```
       netLink.getStartNode(), or 
       netLink.getEndNode(). 
     
```
4. At this point, you may be tempted to navigate further directly from these adjacent nodes. However, the network node objects returned from step 3 might be external node objects in the containing partition, thus, may not have all the references to their adjacent links. If you plan to navigate further from these adjacent nodes, you should always call the following method to ensure that you have the corresponding internal node object that contains all the references to its adjacent links.
```
       networkExplorer.getNetNode(adjacentNode.getId())
     
```
5. From the adjacent network node objects returned from step 4, you can continue navigating the network by repeating step 2 and 3.
6. Since the network node and link objects contain strong references to their adjacent objects, it is important to release any strong references to these objects as soon as you have finished investigating the corresponding part of the network, so that java VM can effectively garbage collect the network of objects that are interconnected to each other. If you have to keep some information from a network object for later, you should manage that information yourself without referencing the network object, or create a standalone object from the network object, and reference the standalone object instead. A standalone object does not contain any reference to other nodes or links.
To create a standalone object from a network object use:
```
       netLink.toStandAloneLink(), or
       netNode.toStandAloneNode().
     
```
Since:

11gR1

Field Summary

Fields
Modifier and Type Field and Description

static int DIRECTION_BACKWARD

static int DIRECTION_BOTH

static int DIRECTION_FORWARD

static int MIN_LINK_LEVEL

Fields
Modifier and Type	Field and Description
`static int`	`DIRECTION_BACKWARD`
`static int`	`DIRECTION_BOTH`
`static int`	`DIRECTION_FORWARD`
`static int`	`MIN_LINK_LEVEL`

Constructor Summary

Constructors
Constructor and Description

NetworkExplorer(NetworkIO reader)
Constructs a NetworkExplorer with empty network updates.

Constructors
Constructor and Description
`NetworkExplorer(NetworkIO reader)` Constructs a NetworkExplorer with empty network updates.

Method Summary

All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods
Modifier and Type	Method and Description
`LeveledNetworkCache`	`getDynamicNetworkCache()` Returns the dynamic network cache.
`HeavyPointOnNet[]`	`getHeavyPointsOnNet(PointOnNet[] points, int[] userDataCategories, int[] featureLayers)`
`LogicalLink`	`getLink(long linkId, int[] userDataCategories)` Returns the standalone logical link.
`LogicalNetLink`	`getNetLink(long linkId, int linkLevel, int partitionId, int[] userDataCategories, int[] featureLayers)` Returns the network link from the specified partition.
`LogicalNetNode`	`getNetNode(long nodeId, int linkLevel, int[] userDataCategories, int[] featureLayers)` Returns the network node from the containing partition.
`LogicalNetNode`	`getNetNodeForDummyExternalNode(int partitionId, long adjacentNodeId, long incidentLinkId, int linkLevel, int[] userDataCategories, int[] featureLayers)` Returns the network node from the containing partition for the dummy external Node.
`NetworkIO`	`getNetworkIO()` Returns the network IO.
`java.util.HashMap<java.lang.Integer,NetworkUpdate>`	`getNetworkUpdates()` Returns the network updates for each link level.
`LogicalNode`	`getNode(long nodeId, int[] userDataCategories)` Returns the standalone node.
`int`	`getNodePartitionId(long nodeId, int linkLevel)` Returns the partition ID for the specified node.
`LogicalPartition`	`getPartition(int partitionId, int linkLevel, int[] userDataCategories, int[] featureLayers)` Returns the partition.
`NetworkIO`	`getReader()` Deprecated. use getNetworkIO()
`static int`	`getReverseDirection(int direction)`
`void`	`setNetworkUpdate(int linkLevel, NetworkUpdate networkUpdate)` Sets the network update object and initialize the dynamic cache.
`void`	`setNetworkUpdates(java.util.HashMap<java.lang.Integer,NetworkUpdate> networkUpdates)` Sets the network update objects and re-initialize the dynamic cache.
`void`	`setReader(NetworkIO reader)` Sets the network reader and the maximum link level.

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

- Field Detail
  - DIRECTION_BOTH
```
public static final int DIRECTION_BOTH
```
    See Also:
    
    Constant Field Values
  - DIRECTION_FORWARD
```
public static final int DIRECTION_FORWARD
```
    See Also:
    
    Constant Field Values
  - DIRECTION_BACKWARD
```
public static final int DIRECTION_BACKWARD
```
    See Also:
    
    Constant Field Values
  - MIN_LINK_LEVEL
```
public static final int MIN_LINK_LEVEL
```
    See Also:
    
    Constant Field Values
- Constructor Detail
  - NetworkExplorer
```
public NetworkExplorer(NetworkIO reader)
                throws LODNetworkException
```
    Constructs a NetworkExplorer with empty network updates.
    
    Parameters:
    
    reader -
    
    Throws:
    
    LODNetworkException
- Method Detail
  - getReverseDirection
```
public static int getReverseDirection(int direction)
```
  - setNetworkUpdates
```
public void setNetworkUpdates(java.util.HashMap<java.lang.Integer,NetworkUpdate> networkUpdates)
```
    Sets the network update objects and re-initialize the dynamic cache. These network update objects will be super imposed to the static network information while the user navigates the network during network analysis.
    
    Parameters:
    
    networkUpdates - network update objects for different link levels
  - setNetworkUpdate
```
public void setNetworkUpdate(int linkLevel,
                             NetworkUpdate networkUpdate)
```
    Sets the network update object and initialize the dynamic cache. These network update objects will be super imposed to the static network information while navigating the network during network analysis.
    
    Parameters:
    
    networkUpdate - network update object
  - getHeavyPointsOnNet
```
public HeavyPointOnNet[] getHeavyPointsOnNet(PointOnNet[] points,
                                             int[] userDataCategories,
                                             int[] featureLayers)
                                      throws LODNetworkException
```
    Throws:
    
    LODNetworkException
  - getLink
```
public LogicalLink getLink(long linkId,
                           int[] userDataCategories)
                    throws LODNetworkException
```
    Returns the standalone logical link. This method first searches for the link in the dynamic network update object. If not found, it reads the link through the NetworkIO object.
    
    Parameters:
    
    linkId - link ID
    
    userDataCategories - If set to true, this method will return a SpatialLink.
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getNode
```
public LogicalNode getNode(long nodeId,
                           int[] userDataCategories)
                    throws LODNetworkException
```
    Returns the standalone node. This method first searches for the node in the dynamic network update object. If not found, it reads the node through the NetworkIO object.
    
    Parameters:
    
    nodeId - node ID
    
    userDataCategories - If set to true, this method will return a SpatialNode.
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getPartition
```
public LogicalPartition getPartition(int partitionId,
                                     int linkLevel,
                                     int[] userDataCategories,
                                     int[] featureLayers)
                              throws LODNetworkException
```
    Returns the partition. This method first searches for the partition in the dynamic network update object. If not found, it reads the partition through the NetworkIO object.
    
    Parameters:
    
    partitionId - partition ID
    
    linkLevel - link level
    
    userDataCategories -
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getNodePartitionId
```
public int getNodePartitionId(long nodeId,
                              int linkLevel)
                       throws LODNetworkException
```
    Returns the partition ID for the specified node.
    
    Parameters:
    
    nodeId - node ID
    
    linkLevel - link level
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getNetNode
```
public LogicalNetNode getNetNode(long nodeId,
                                 int linkLevel,
                                 int[] userDataCategories,
                                 int[] featureLayers)
                          throws LODNetworkException
```
    Returns the network node from the containing partition. The returned network node contains references to all its adjacent links.
    
    Parameters:
    
    nodeId - node ID
    
    linkLevel - link level
    
    userDataCategories -
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getNetNodeForDummyExternalNode
```
public LogicalNetNode getNetNodeForDummyExternalNode(int partitionId,
                                                     long adjacentNodeId,
                                                     long incidentLinkId,
                                                     int linkLevel,
                                                     int[] userDataCategories,
                                                     int[] featureLayers)
                                              throws LODNetworkException
```
    Returns the network node from the containing partition for the dummy external Node. The only reliable information in a dummy external node is the ID of the containing partition. The returned network node contains references to all its adjacent links.
    
    Parameters:
    
    partitionId - ID of the partition that owns the external node
    
    adjacentNodeId - ID of the node on the other side of the incident link
    
    incidentLinkId - ID of the link that is incident to the external node
    
    linkLevel - link level of the containing partition
    
    userDataCategories -
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - getNetLink
```
public LogicalNetLink getNetLink(long linkId,
                                 int linkLevel,
                                 int partitionId,
                                 int[] userDataCategories,
                                 int[] featureLayers)
                          throws LODNetworkException
```
    Returns the network link from the specified partition.
    
    Parameters:
    
    linkId - link ID
    
    linkLevel - link level
    
    partitionId - ID of the partition that owns the link
    
    userDataCategories -
    
    Returns:
    
    Throws:
    
    LODNetworkException
  - setReader
```
public void setReader(NetworkIO reader)
               throws LODNetworkException
```
    Sets the network reader and the maximum link level.
    
    Parameters:
    
    reader - network reader
    
    Throws:
    
    LODNetworkException
  - getReader
```
public NetworkIO getReader()
```
    Deprecated. use getNetworkIO()
    
    Returns the network reader.
    
    Returns:
  - getNetworkIO
```
public NetworkIO getNetworkIO()
```
    Returns the network IO.
    
    Returns:
  - getNetworkUpdates
```
public java.util.HashMap<java.lang.Integer,NetworkUpdate> getNetworkUpdates()
```
    Returns the network updates for each link level.
    
    Returns:
  - getDynamicNetworkCache
```
public LeveledNetworkCache getDynamicNetworkCache()
```
    Returns the dynamic network cache.
    
    Returns:

Class NetworkExplorer

Field Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Field Detail

DIRECTION_BOTH

DIRECTION_FORWARD

DIRECTION_BACKWARD

MIN_LINK_LEVEL

Constructor Detail

NetworkExplorer

Method Detail

getReverseDirection

setNetworkUpdates

setNetworkUpdate

getHeavyPointsOnNet

getLink

getNode

getPartition

getNodePartitionId

getNetNode

getNetNodeForDummyExternalNode

getNetLink

setReader

getReader

getNetworkIO

getNetworkUpdates

getDynamicNetworkCache