review comments

packages/http-client-java/CONTRIBUTING.md

@@ -8,6 +8,16 @@ Install [Java](https://docs.microsoft.com/java/openjdk/download) 17 or above. (V
 
 Install [Maven](https://maven.apache.org/download.cgi). (Verify by running `mvn --version`)
 
+## Project Structure
+
+The TypeSpec Java Emitter Library is a Node.js package.
+It publishes to [npm `@typespec/http-client-java`](https://www.npmjs.com/package/@typespec/http-client-java).
+
+As a Node.js package, the entry of the library is written in TypeScript, under `emitter` folder.
+
+As a Java code generator, part of the implementation is written in Java, under `generator` folder.
+Java code is packaged into a JAR file, and included in the Node.js package. The JAR file is called at runtime by TypeScript code.
+
 ## Build and Pack
 
 ["Setup.ps1" script](https://github.com/microsoft/typespec/blob/main/packages/http-client-java/Setup.ps1) builds TypeScript code and Java code, and packs them into "typespec-http-client-java-[version].tgz".
@@ -29,23 +39,32 @@ Their folder structure is identical. In the following sub-sections, the script o
 
 ### Set-up the environment
 
-"Setup.ps1" script builds the emitter, and sets up the test environment.
+["Setup.ps1" script in test module](https://github.com/microsoft/typespec/blob/main/packages/http-client-java/generator/http-client-generator-clientcore-test/Setup.ps1) builds the emitter, and sets up the test environment.
+
+Internally, it does
+
+1. Build the `@typespec/http-client-java` tgz locally. See [Build and Pack](#build-and-pack).
+2. Re-install the tgz (along with other dependencies) in the test module.
 
 ### Generate the test code
 
 If the feature or bug fix involves code change on generated code, you will need to re-generate the test code in one or both of the test modules.
 
-"Generate.ps1" script (internally it calls "Setup.ps1" script as 1st step) generates the code for end-to-end testing.
-The code is generated from TypeSpec source in [`@typespec/http-specs` package](https://www.npmjs.com/package/@typespec/http-specs).
+["Generate.ps1" script](https://github.com/microsoft/typespec/blob/main/packages/http-client-java/generator/http-client-generator-clientcore-test/Generate.ps1) (internally it calls the "Setup.ps1" script) generates the code for end-to-end testing.
+The code is generated from TypeSpec source from [npm `@typespec/http-specs` package](https://www.npmjs.com/package/@typespec/http-specs).
 
 ### Run the end-to-end tests
 
-1. Start the test server with `npm run spector-serve` (or `npm run spector-start` to start as a background process, `npm run spector-stop` to stop)
-2. Run all the Java tests in the module
+["Spector-Tests.ps1" script](https://github.com/microsoft/typespec/blob/main/packages/http-client-java/generator/http-client-generator-clientcore-test/Spector-Tests.ps1) starts the spector server, and run all the Java tests.
+
+When writing / updating Java tests, you can manually
+
+1. Start the test server with `npm run spector-serve` (or `npm run spector-start` to start as a background process, `npm run spector-stop` to stop).
+2. Run the Java tests in the module.
 
 ## Format Code
 
-Before creating pull request, you are required to format the code.
+Before creating pull request, the code is required to be well-formatted.
 
 Run `npm run format` in "packages/http-client-java" folder.
 It formats TypeScript code as well as Java code.