JsonJacksonFormat.java 文件源码

/**
 * Parse a text-format message from {@code input} and merge the contents into {@code builder}.
 * Extensions will be recognized if they are registered in {@code extensionRegistry}.
 * @throws IOException
 */
public void merge(JsonParser parser,
                         ExtensionRegistry extensionRegistry,
                         Message.Builder builder) throws IOException {

    JsonToken token = parser.nextToken();
    if (token.equals(JsonToken.START_OBJECT)) {
        token = parser.nextToken();
    }
    while (token != null && !token.equals(JsonToken.END_OBJECT)) {
        mergeField(parser, extensionRegistry, builder);
        token = parser.nextToken();
    }

    // Test to make sure the tokenizer has reached the end of the stream.
    if (parser.nextToken() != null) {
        throw new RuntimeException("Expecting the end of the stream, but there seems to be more data!  Check the input for a valid JSON format.");
    }
}