net.openhft.chronicle.hash.serialization

Interface BytesReader<E>

Type Parameters:

E - the type of the object demarshalled

All Superinterfaces:

Serializable

All Known Subinterfaces:

DeserializationFactoryConfigurableBytesReader<E,R>

public interface BytesReader<E>
extends Serializable

Deserializer (object from Bytes, mirroring the BytesWriter, i. e. assuming the length of the serialized form isn't written in the beginning of the serialized form itself, but managed by ChronicleHash implementation and passed to the reading methods.

Implementation example:

 class LongPair { long first, second; }
 
 enum LongPairArrayReader implements BytesReader<LongPair[]> {
     INSTANCE;

     @Override
     public LongPair[] read(Bytes bytes, long size) {
         return read(bytes, size, null);
     }

     @Override
     public LongPair[] read(Bytes bytes, long size, LongPair[] toReuse) {
         if (size > Integer.MAX_VALUE * 16L)
             throw new IllegalStateException("LongPair[] size couldn't be " + (size / 16L));
         int resLen = (int) (size / 16L);
         LongPair[] res;
         if (toReuse != null) {
             if (toReuse.length == resLen) {
                 res = toReuse;
             } else {
                 res = Arrays.copyOf(toReuse, resLen);
             }
         } else {
             res = new LongPair[resLen];
         }
         for (int i = 0; i < resLen; i++) {
             LongPair pair = res[i];
             if (pair == null)
                 res[i] = pair = new LongPair();
             pair.first = bytes.readLong();
             pair.second = bytes.readLong();
         }
         return res;
     }
 }

See Also:

BytesWriter

Method Summary

Methods

Modifier and Type	Method and Description
E	read(Bytes bytes, long size) Reads and returns the object from [position(), position() + size] bytes of the given Bytes.
E	read(Bytes bytes, long size, E toReuse) Similar to read(Bytes, long), but should attempt to reuse the given object, i.

Method Detail

read

E read(Bytes bytes,
     long size)

Reads and returns the object from [position(), position() + size] bytes of the given Bytes.

Implementation of this method should increment the bytes' position by the given size, i. e. "consume" the bytes of the deserialized object. It must not alter the bytes' limit and contents.

Parameters:

bytes - the Bytes to read the object from

size - the size of the serialized form of the returned object

Returns:

the object read from the bytes

See Also:

BytesWriter.write(Bytes, Object), read(Bytes, long, Object)

read

E read(Bytes bytes,
     long size,
     @Nullable
     E toReuse)

Similar to read(Bytes, long), but should attempt to reuse the given object, i. e. to read the deserialized data into the given instance. If it is possible, this objects than returned from this method. If it isn't possible for any reason, a new object should be created and returned, just like in read(Bytes, long) method. The given object could be null, in this case this method should behave exactly the same as read(Bytes, long) method does.

Parameters:

bytes - the Bytes to read the object from

size - the size of the serialized form of the returned object

toReuse - the object to read the deserialized data into

Returns:

the object read from the bytes, either reused or newly created

See Also:

read(Bytes, long)