View (couchbase-lite-java-core API)

java.lang.Object
- com.couchbase.lite.View

All Implemented Interfaces:

ViewStoreDelegate
```
public final class View
extends java.lang.Object
implements ViewStoreDelegate
```
Represents a view available in a database.

Nested Class Summary

Nested Classes
Modifier and Type Class and Description

static class View.TDViewCollation

Nested Classes
Modifier and Type	Class and Description
`static class`	`View.TDViewCollation`

Constructor Summary

Constructors
Modifier Constructor and Description

protected View(Database database, java.lang.String name, boolean create)

Constructors
Modifier	Constructor and Description
`protected`	`View(Database database, java.lang.String name, boolean create)`

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method and Description
`void`	`close()`
`Query`	`createQuery()` Creates a new query object for this view.
`void`	`delete()` Deletes the view, persistently.
`void`	`deleteIndex()` Deletes the view's persistent index.
`protected java.util.List<java.util.Map<java.lang.String,java.lang.Object>>`	`dump()`
`static ViewCompiler`	`getCompiler()` The registered object, if any, that can compile map/reduce functions from source code.
`int`	`getCurrentTotalRows()`
`protected Database`	`getDatabase()` Get the database that owns this view.
`java.lang.String`	`getDocumentType()` Get document type.
`long`	`getLastSequenceIndexed()` Get the last sequence number indexed so far.
`Mapper`	`getMap()` The map function that controls how index rows are created from documents.
`java.lang.String`	`getMapVersion()` The current map version string.
`java.lang.String`	`getName()` Get the name of the view.
`Reducer`	`getReduce()` The optional reduce function, which aggregates together multiple rows.
`int`	`getTotalRows()` Get total number of rows in the view.
`protected java.util.List<View>`	`getViewsInGroup()` Get all views that have the same prefix if specified.
`boolean`	`isStale()` Is the view's index currently out of date?
`static java.lang.Object`	`keyForPrefixMatch(java.lang.Object key, int depth)` Changes a maxKey into one that also extends to any key it matches as a prefix
`java.util.List<QueryRow>`	`query(QueryOptions options)` Queries the view.
`void`	`setCollation(View.TDViewCollation collation)`
`static void`	`setCompiler(ViewCompiler compiler)` Registers an object that can compile map/reduce functions from source code.
`void`	`setDocumentType(java.lang.String docType)` Set document type.
`boolean`	`setMap(Mapper mapBlock, java.lang.String version)` Defines a view that has no reduce function.
`boolean`	`setMapReduce(Mapper mapBlock, Reducer reduceBlock, java.lang.String version)` Defines a view's functions.
`java.lang.String`	`toString()`
`static double`	`totalValues(java.util.List<java.lang.Object> values)` Utility function to use in reduce blocks.
`Status`	`updateIndex()` Updates the view's index (incrementally) if necessary.
`Status`	`updateIndexAlone()` Updates the view's index (incrementally) if necessary.
`protected Status`	`updateIndexes(java.util.List<View> views)` Update multiple view indexes at once.

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

- Constructor Detail
  - View
```
protected View(Database database,
               java.lang.String name,
               boolean create)
        throws CouchbaseLiteException
```
    Throws:
    
    CouchbaseLiteException
- Method Detail
  - getMap
```
public Mapper getMap()
```
    The map function that controls how index rows are created from documents.
    
    Specified by:
    
    getMap in interface ViewStoreDelegate
  - getReduce
```
public Reducer getReduce()
```
    The optional reduce function, which aggregates together multiple rows.
    
    Specified by:
    
    getReduce in interface ViewStoreDelegate
  - getMapVersion
```
public java.lang.String getMapVersion()
```
    Description copied from interface: ViewStoreDelegate
    
    The current map version string. If this changes, the storage's -setVersion: method will be called to notify it, so it can invalidate the _index.
    
    Specified by:
    
    getMapVersion in interface ViewStoreDelegate
  - getDocumentType
```
public java.lang.String getDocumentType()
```
    Get document type.
    
    Specified by:
    
    getDocumentType in interface ViewStoreDelegate
  - setDocumentType
```
public void setDocumentType(java.lang.String docType)
```
    Set document type. If the document type is set, only documents whose "type" property is equal to its value will be passed to the map block and indexed. This can speed up indexing. Just like the map block, this property is not persistent; it needs to be set at runtime before the view is queried. And if its value changes, the view's version also needs to change.
  - getDatabase
```
protected Database getDatabase()
```
    Get the database that owns this view.
  - getName
```
public java.lang.String getName()
```
    Get the name of the view.
  - setMapReduce
```
public boolean setMapReduce(Mapper mapBlock,
                            Reducer reduceBlock,
                            java.lang.String version)
```
    Defines a view's functions.
    The view's definition is given as a class that conforms to the Mapper or Reducer interface (or null to delete the view). The body of the block should call the 'emit' object (passed in as a paramter) for every key/value pair it wants to write to the view.
    Since the function itself is obviously not stored in the database (only a unique string idenfitying it), you must re-define the view on every launch of the app! If the database needs to rebuild the view but the function hasn't been defined yet, it will fail and the view will be empty, causing weird problems later on.
    It is very important that this block be a law-abiding map function! As in other languages, it must be a "pure" function, with no side effects, that always emits the same values given the same input document. That means that it should not access or change any external state; be careful, since callbacks make that so easy that you might do it inadvertently! The callback may be called on any thread, or on multiple threads simultaneously. This won't be a problem if the code is "pure" as described above, since it will as a consequence also be thread-safe.
  - setMap
```
public boolean setMap(Mapper mapBlock,
                      java.lang.String version)
```
    Defines a view that has no reduce function. See setMapReduce() for more information.
  - isStale
```
public boolean isStale()
```
    Is the view's index currently out of date?
  - getTotalRows
```
public int getTotalRows()
```
    Get total number of rows in the view. The view's index will be updated if needed before returning the value.
  - getLastSequenceIndexed
```
public long getLastSequenceIndexed()
```
    Get the last sequence number indexed so far.
  - deleteIndex
```
public void deleteIndex()
```
    Deletes the view's persistent index. It will be regenerated on the next query.
  - delete
```
public void delete()
```
    Deletes the view, persistently.
    NOTE: It should be - (void) deleteView;
  - createQuery
```
public Query createQuery()
```
    Creates a new query object for this view. The query can be customized and then executed.
  - totalValues
```
public static double totalValues(java.util.List<java.lang.Object> values)
```
    Utility function to use in reduce blocks. Totals an array of Numbers.
  - getCompiler
```
public static ViewCompiler getCompiler()
```
    The registered object, if any, that can compile map/reduce functions from source code.
  - setCompiler
```
public static void setCompiler(ViewCompiler compiler)
```
    Registers an object that can compile map/reduce functions from source code.
  - getCurrentTotalRows
```
public int getCurrentTotalRows()
```
  - close
```
public void close()
```
  - setCollation
```
public void setCollation(View.TDViewCollation collation)
```
  - updateIndex
```
public Status updateIndex()
                   throws CouchbaseLiteException
```
    Updates the view's index (incrementally) if necessary. Multiple views whose name starts with the same prefix before the slash as the view's will be indexed together at once.
    
    Returns:
    
    Status OK if updated or NOT_MODIFIED if already up-to-date.
    
    Throws:
    
    CouchbaseLiteException
  - updateIndexAlone
```
public Status updateIndexAlone()
                        throws CouchbaseLiteException
```
    Updates the view's index (incrementally) if necessary. Only the view's index alone will be updated.
    
    Returns:
    
    Status OK if updated or NOT_MODIFIED if already up-to-date.
    
    Throws:
    
    CouchbaseLiteException
  - updateIndexes
```
protected Status updateIndexes(java.util.List<View> views)
                        throws CouchbaseLiteException
```
    Update multiple view indexes at once.
    
    Parameters:
    
    views - a list of views whose index will be updated.
    
    Throws:
    
    CouchbaseLiteException
  - getViewsInGroup
```
protected java.util.List<View> getViewsInGroup()
```
    Get all views that have the same prefix if specified. The prefix ends with slash '/' character.
    
    Returns:
    
    An array of all views with the same prefix.
  - query
```
public java.util.List<QueryRow> query(QueryOptions options)
                               throws CouchbaseLiteException
```
    Queries the view. Does NOT first update the index.
    
    Parameters:
    
    options - The options to use.
    
    Returns:
    
    An array of QueryRow objects.
    
    Throws:
    
    CouchbaseLiteException
  - keyForPrefixMatch
```
public static java.lang.Object keyForPrefixMatch(java.lang.Object key,
                                                 int depth)
```
    Changes a maxKey into one that also extends to any key it matches as a prefix
  - dump
```
protected java.util.List<java.util.Map<java.lang.String,java.lang.Object>> dump()
```
  - toString
```
public java.lang.String toString()
```
    Overrides:
    
    toString in class java.lang.Object

Class View

Nested Class Summary

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Constructor Detail

View

Method Detail

getMap

getReduce

getMapVersion

getDocumentType

setDocumentType

getDatabase

getName

setMapReduce

setMap

isStale

getTotalRows

getLastSequenceIndexed

deleteIndex

delete

createQuery

totalValues

getCompiler

setCompiler

getCurrentTotalRows

close

setCollation

updateIndex

updateIndexAlone

updateIndexes

getViewsInGroup

query

keyForPrefixMatch

dump

toString