diff --git a/java/README.md b/java/README.md index 060d9ac6b1..83f91e186c 100644 --- a/java/README.md +++ b/java/README.md @@ -17,9 +17,10 @@ rather build without Maven, see below. http://maven.apache.org/ -2) Build the C++ code, or obtain a binary distribution of protoc. If - you install a binary distribution, make sure that it is the same - version as this package. If in doubt, run: +2) Build the C++ code, or obtain a binary distribution of protoc (see + the toplevel [README.md](../README.md)). If you install a binary + distribution, make sure that it is the same version as this package. + If in doubt, run: $ protoc --version @@ -44,36 +45,25 @@ rather build without Maven, see below. The .jar will be placed in the "target" directory. -Installation - 'Lite' Version - With Maven -========================================== - -Building the 'lite' version of the Java Protocol Buffers library is -the same as building the full version, except that all commands are -run using the 'lite' profile. (see -http://maven.apache.org/guides/introduction/introduction-to-profiles.html) - -E.g. to install the lite version of the jar, you would run: +The above instructions will install 3 maven artifacts: - $ mvn install -P lite - -The resulting artifact has the 'lite' classifier. To reference it -for dependency resolution, you would specify it as: - -``` - - com.google.protobuf - protobuf-java - ${version} - lite - -``` + * protobuf-java: The core Java Protocol Buffers library. Most users only + need this artifact. + * protobuf-lite: The lite version of core Java Protobuf Buffers library. It + is a subset of the core library and is used together with + the 'lite' code generator flag to reduce generated code size + for mobile. + * protobuf-java-util: Utilities to work with protos. It contains JSON support + as well as utilities to work with proto3 well-known + types. Installation - Without Maven ============================ If you would rather not install Maven to build the library, you may follow these instructions instead. Note that these instructions skip -running unit tests. +running unit tests and only describes how to install the core protobuf +library (without the util package). 1) Build the C++ code, or obtain a binary distribution of protoc. If you install a binary distribution, make sure that it is the same @@ -86,15 +76,50 @@ running unit tests. 2) Invoke protoc to build DescriptorProtos.java: - $ protoc --java_out=src/main/java -I../src \ + $ protoc --java_out=core/src/main/java -I../src \ ../src/google/protobuf/descriptor.proto -3) Compile the code in src/main/java using whatever means you prefer. +3) Compile the code in core/src/main/java using whatever means you prefer. 4) Install the classes wherever you prefer. -Usage -===== +Compatibility Notice +==================== + +* Protobuf minor version releases are backwards-compatible. If your code + can build/run against the old version, it's expected to build/run against + the new version as well. Both binary compatibility and source compatbility + are guaranteed for minor version releases if the user follows the guideline + described in this section. + +* Protobuf major version releases may also be backwards-compatbile with the + last release of the previous major version. See the release notice for more + details. + +* APIs marked with the @ExperimentalApi annotation are subject to change. They + can be modified in any way, or even removed, at any time. Don't use them if + compatiblity is needed. If your code is a library itself (i.e. it is used on + the CLASSPATH of users outside your own control), you should not use + experimental APIs, unless you repackage them (e.g. using ProGuard). + +* Deprecated non-experimental APIs will be removed two years after the release + in which they are first deprecated. You must fix your references before this + time. If you don't, any manner of breakage could result (you are not + guaranteed a compilation error). + +* Protobuf message interfaces/classes are designed to be subclassed by protobuf + generated code only. Do not subclass these message interfaces/classes + yourself. We may add new methods to the message interfaces/classes which will + break your own subclasses. + +* Don't use any method/class that is marked as "used by generated code only". + Such methods/classes are subject to change. + +* Protobuf LITE runtime APIs are not stable yet. They are subject to change even + in minor version releases. + +Documentation +============= The complete documentation for Protocol Buffers is available via the web at: