net.openhft.chronicle.hash.serialization

Interface StatefulCopyable<T extends StatefulCopyable<T>>

Type Parameters:

T - the type of marshaller, implementing this interface

All Known Subinterfaces:

DataAccess<T>

All Known Implementing Classes:

ListMarshaller, MapMarshaller, SetMarshaller

public interface StatefulCopyable<T extends StatefulCopyable<T>>

Stateful implementations of marshaller interfaces (SizedReader, SizedWriter, BytesReader, BytesWriter, DataAccess), configured for ChronicleMap or ChronicleSet in builder, should implement the StatefulCopyable interface. The marshaller instance is populated for each site by copy() method.

For example, see StringBytesReader implementation:

 public class StringBytesReader
         implements BytesReader<String>, StatefulCopyable<StringBytesReader> {

     private final StringBuilder sb = new StringBuilder();

     @NotNull
     @Override
     public String read(Bytes in, @Nullable String using) {
         sb.setLength(0);
         in.readUtf8(sb);
         return sb.toString();
     }

     @Override
     public StringBytesReader copy() {
         return new StringBytesReader();
     }
 }
 

Method Summary

Modifier and Type	Method and Description
T	copy() Creates a copy of this marshaller, with independent state.
static <T> T	copyIfNeeded(T possiblyStatefulCopyable) Checks if possiblyStatefulCopyable implements StatefulCopyable, then returns copy() of it, otherwise returns the possiblyStatefulCopyable itself.

Method Detail

copy

T copy()

Creates a copy of this marshaller, with independent state. The current state itself shouldn't be copied (it could be "clear" in the copy), only "configuration" of the instance, on which copy() is called, should be inherited in the copy (e. g. the class of objects serialized). So, copy() should be transitive, i. e. marshaller.copy() and marshaller.copy().copy() should result to identical instances.

The state of the instance on which copy() is called shouldn't be changed.

If some marshaller is ought to implement StatefulCopyable interface (e. g. DataAccess) but is stateless actually, it could return this from this method.

Returns:

the copy if this marshaller with the same configuration, but independent state

copyIfNeeded

static <T> T copyIfNeeded(T possiblyStatefulCopyable)

Checks if possiblyStatefulCopyable implements StatefulCopyable, then returns copy() of it, otherwise returns the possiblyStatefulCopyable itself.

Type Parameters:

T - the type of the passed instance

Parameters:

possiblyStatefulCopyable - the instance to copy() if it implements StatefulCopyable, or to return without modification

Returns:

the copy of the passed instance with independent state, of the instance back, if it doesn't implement StatefulCopyable