View (Exonum Java Binding Parent 0.8.0 API)

java.lang.Object
- com.exonum.binding.core.proxy.AbstractNativeProxy
- - com.exonum.binding.core.storage.database.View

Direct Known Subclasses:

Fork, Snapshot
```
public abstract class View
extends AbstractNativeProxy
```
Represents a view of the database.
There are two sub-types:
- A snapshot, which is a read-only and immutable view.
- A fork, which is a read-write view.
As in some cases the clients need to detect any changes made to a database, a view also holds a modification counter, which any clients changing the database state must notify.
See Also:

Snapshot, Fork

Field Summary
- Fields inherited from class com.exonum.binding.core.proxy.AbstractNativeProxy
  nativeHandle

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`boolean`	`canModify()`	Returns true if this view allows modifications to the database state; false if it is immutable.
`Optional<StorageIndex>`	`findOpenIndex(IndexAddress address)`	Finds an open index by the given address.
`Cleaner`	`getCleaner()`	Returns the cleaner of this view.
`long`	`getViewNativeHandle()`	Returns a native handle of this view.
`void`	`registerIndex(StorageIndex index)`	Registers a new index created with this view.

Methods inherited from class com.exonum.binding.core.proxy.AbstractNativeProxy
getNativeHandle, isValidHandle

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

- Method Detail
  - canModify
```
public boolean canModify()
```
    Returns true if this view allows modifications to the database state; false if it is immutable.
  - getViewNativeHandle
```
public long getViewNativeHandle()
```
    Returns a native handle of this view.
    
    Throws:
    
    IllegalStateException - if the view is invalid (closed or nullptr)
  - findOpenIndex
```
public Optional<StorageIndex> findOpenIndex(IndexAddress address)
```
    Finds an open index by the given address.
    This method is for internal use. It is not designed to be used by services, rather by index factories.
    
    Parameters:
    
    address - the index address
    
    Returns:
    
    an index with the given address; or Optional.empty() if no index with such address was open in this view
  - registerIndex
```
public void registerIndex(StorageIndex index)
```
    Registers a new index created with this view.
    This method is for internal use. It is not designed to be used by services, rather by index factories.
    
    Parameters:
    
    index - a new index to register
    
    Throws:
    
    IllegalArgumentException - if the index is already registered
    
    See Also:
    
    findOpenIndex(IndexAddress)
  - getCleaner
```
public Cleaner getCleaner()
```
    Returns the cleaner of this view.