Package com.google.protobuf

Class LazyFieldLite

java.lang.Object
com.google.protobuf.LazyFieldLite
Direct Known Subclasses:
LazyField
public class LazyFieldLite extends Object
LazyFieldLite encapsulates the logic of lazily parsing message fields. It stores the message in a ByteString initially and then parses it on-demand.

LazyFieldLite is thread-compatible: concurrent reads are safe once the proto that this LazyFieldLite is a part of is no longer being mutated by its Builder. However, explicit synchronization is needed under read/write situations.

When a LazyFieldLite is used in the context of a MessageLite object, its behavior is considered to be immutable and none of the setter methods in its API are expected to be invoked. All of the getters are expected to be thread-safe. When used in the context of a MessageLite.Builder, setters can be invoked, but there is no guarantee of thread safety.

TODO: Consider splitting this class's functionality and put the mutable methods into a separate builder class to allow us to give stronger compile-time guarantees.

This class is internal implementation detail of the protobuf library, so you don't need to use it directly.

  • Field Details

    • value

      protected volatile MessageLite value
      The parsed value. When this is null and a caller needs access to the MessageLite value, then delayedBytes will be parsed lazily at that time.

  • Constructor Details

    • LazyFieldLite

      public LazyFieldLite(ExtensionRegistryLite extensionRegistry, ByteString bytes)
      Constructs a LazyFieldLite with bytes that will be parsed lazily.

    • LazyFieldLite

      public LazyFieldLite()
      Constructs a LazyFieldLite with no contents, and no ability to parse extensions.

  • Method Details

    • fromValue

      public static LazyFieldLite fromValue(MessageLite value)
      Constructs a LazyFieldLite instance with a value. The LazyFieldLite may not be able to parse the extensions in the value as it has no ExtensionRegistry.

    • equals

      public boolean equals(Object o)
      Overrides:
      equals in class Object

    • hashCode

      public int hashCode()
      Overrides:
      hashCode in class Object

    • containsDefaultInstance

      public boolean containsDefaultInstance()
      Determines whether this LazyFieldLite instance represents the default instance of this type.

    • clear

      public void clear()
      Clears the value state of this instance.

      LazyField is not thread-safe for write access. Synchronizations are needed under read/write situations.

    • set

      public void set(LazyFieldLite other)
      Overrides the contents of this LazyField.

      LazyField is not thread-safe for write access. Synchronizations are needed under read/write situations.

    • getValue

      public MessageLite getValue(MessageLite defaultInstance)
      Returns message instance. It may do some thread-safe delayed parsing of bytes.
      Parameters:
      defaultInstance - its message's default instance. It's also used to get parser for the message type.

    • setValue

      public MessageLite setValue(MessageLite value)
      Sets the value of the instance and returns the old value without delay parsing anything.

      LazyField is not thread-safe for write access. Synchronizations are needed under read/write situations.

    • merge

      public void merge(LazyFieldLite other)
      Merges another instance's contents. In some cases may drop some extensions if both fields contain data. If the other field has an ExtensionRegistry but this does not, then this field will copy over that ExtensionRegistry.

      LazyField is not thread-safe for write access. Synchronizations are needed under read/write situations.

    • mergeFrom

      public void mergeFrom(CodedInputStream input, ExtensionRegistryLite extensionRegistry) throws IOException
      Merges another instance's contents from a stream.

      LazyField is not thread-safe for write access. Synchronizations are needed under read/write situations.

      Throws:
      IOException

    • setByteString

      public void setByteString(ByteString bytes, ExtensionRegistryLite extensionRegistry)
      Sets this field with bytes to delay-parse.

    • getSerializedSize

      public int getSerializedSize()
      Due to the optional field can be duplicated at the end of serialized bytes, which will make the serialized size changed after LazyField parsed. Be careful when using this method.

    • toByteString

      public ByteString toByteString()
      Returns a BytesString for this field in a thread-safe way.

    • ensureInitialized

      protected void ensureInitialized(MessageLite defaultInstance)
      Might lazily parse the bytes that were previously passed in. Is thread-safe.