Package com.apple.foundationdb.record.query.plan.temp

Class MessageValue

java.lang.Object

com.apple.foundationdb.record.query.plan.temp.MessageValue

@API(EXPERIMENTAL)
public class MessageValue
extends Object

A utility class for extracting data and meta-data from Protocol Buffer Messages, as used in the Record Layer.

Method Summary

Modifier and Type	Method	Description
static Descriptors.FieldDescriptor	findFieldDescriptorOnMessage(MessageOrBuilder message, String fieldName)
static Object	getFieldOnMessage(MessageOrBuilder message, String fieldName)	Get the value of the field with the given field name on the given message.
static Object	getFieldValue(MessageOrBuilder message, List<String> fieldNames)	Get the value of the (nested) field on the path from the message defined by fieldNames.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Method Detail

getFieldValue

@Nullable
public static Object getFieldValue(@Nonnull
                                   MessageOrBuilder message,
                                   @Nonnull
                                   List<String> fieldNames)

Get the value of the (nested) field on the path from the message defined by fieldNames. The given field names define a path through the nested structure of the given message; this method traverses that path and returns the value at the leaf, using the return semantics of getFieldOnMessage(MessageOrBuilder, String).

Parameters:

message - a message

fieldNames - a list of field names defining a path starting at message

Returns:

the value at the end of hte path

getFieldOnMessage

@Nullable
public static Object getFieldOnMessage(@Nonnull
                                       MessageOrBuilder message,
                                       @Nonnull
                                       String fieldName)

Get the value of the field with the given field name on the given message. If the field is repeated, the repeated values are combined into a list. If the field has a message type, the value is returned as a Message of that type. Otherwise, the field is returned as a primitive.

Parameters:

message - a message or builder to extract the field from

fieldName - the field to extract

Returns:

the value of the field as described above

findFieldDescriptorOnMessage

@Nonnull
public static Descriptors.FieldDescriptor findFieldDescriptorOnMessage(@Nonnull
                                                                       MessageOrBuilder message,
                                                                       @Nonnull
                                                                       String fieldName)