MapField (Protocol Buffers [Core] 4.0.0-rc-2 API)

java.lang.Object
- com.google.protobuf.MapField<K,V>

```
public class MapField<K,V>
extends java.lang.Object
```
Internal representation of map fields in generated messages.
This class supports accessing the map field as a Map to be used in generated API and also supports accessing the field as a List to be used in reflection API. It keeps track of where the data is currently stored and do necessary conversions between map and list.
This class is a protobuf implementation detail. Users shouldn't use this class directly.
THREAD-SAFETY NOTE: Read-only access is thread-safe. Users can call getMap() and getList() concurrently in multiple threads. If write-access is needed, all access must be synchronized.

Field Summary

Fields
Modifier and Type Field Description

static com.google.protobuf.MutabilityOracle IMMUTABLE

Method Summary

All Methods Static Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`void`	`clear()`
`MapField<K,V>`	`copy()`	Returns a deep copy of this MapField.
`static <K,V> MapField<K,V>`	`emptyMapField(MapEntry<K,V> defaultEntry)`	Returns an immutable empty MapField.
`void`	`ensureMutable()`
`boolean`	`equals(java.lang.Object object)`
`java.util.Map<K,V>`	`getMap()`	Returns the content of this MapField as a read-only Map.
`java.util.Map<K,V>`	`getMutableMap()`	Gets a mutable Map view of this MapField.
`int`	`hashCode()`
`boolean`	`isMutable()`	Returns whether this field can be modified.
`void`	`makeImmutable()`	Makes this list immutable.
`void`	`mergeFrom(MapField<K,V> other)`
`static <K,V> MapField<K,V>`	`newMapField(MapEntry<K,V> defaultEntry)`	Creates a new mutable empty MapField.

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

Field Detail

IMMUTABLE

public static final com.google.protobuf.MutabilityOracle IMMUTABLE

Method Detail
- emptyMapField
```
public static <K,V> MapField<K,V> emptyMapField(MapEntry<K,V> defaultEntry)
```
  Returns an immutable empty MapField.
- newMapField
```
public static <K,V> MapField<K,V> newMapField(MapEntry<K,V> defaultEntry)
```
  Creates a new mutable empty MapField.
- getMap
```
public java.util.Map<K,V> getMap()
```
  Returns the content of this MapField as a read-only Map.
- getMutableMap
```
public java.util.Map<K,V> getMutableMap()
```
  Gets a mutable Map view of this MapField.
- mergeFrom
```
public void mergeFrom(MapField<K,V> other)
```
- clear
```
public void clear()
```
- equals
```
public boolean equals(java.lang.Object object)
```
  Overrides:
  
  equals in class java.lang.Object
- hashCode
```
public int hashCode()
```
  Overrides:
  
  hashCode in class java.lang.Object
- copy
```
public MapField<K,V> copy()
```
  Returns a deep copy of this MapField.
- makeImmutable
```
public void makeImmutable()
```
  Makes this list immutable. All subsequent modifications will throw an UnsupportedOperationException.
- isMutable
```
public boolean isMutable()
```
  Returns whether this field can be modified.
- ensureMutable
```
public void ensureMutable()
```