add a function and update readme

Author: wsw-stack

.gitignore

@@ -7,6 +7,7 @@
 .idea
 *.iml
 /target/
+/src/test/resources/xml_files
 
 /bin/
 build

README.md

@@ -40,7 +40,7 @@ Bug fixes, code improvements, and unit test coverage changes are welcome! Becaus
 # Build Instructions
 
 The org.json package can be built from the command line, Maven, and Gradle. The unit tests can be executed from Maven, Gradle, or individually in an IDE e.g. Eclipse.
- 
+
 **Building from the command line**
 
 *Build the class files from the package root directory src/main/java*
@@ -83,7 +83,7 @@ java -cp .:json-java.jar Test (Unix Systems)
 {"abc":"def"}
 ```
 
- 
+
 **Tools to build the package and execute the unit tests**
 
 Execute the test suite with Maven:
@@ -109,6 +109,23 @@ gradlew testWithStrictMode
 mvn test -P test-strict-mode 
 ```
 
+# Milestone 2
+
+For the Milestone 2 of SWE262P, 2 new functions were added:
+
+```java
+static JSONObject toJSONObject(Reader reader, JSONPointer path) 
+static JSONObject toJSONObject(Reader reader, JSONPointer path, JSONObject replacement) 
+```
+
+The first one takes in 2 parameters, a `Reader` object which contains some XML input and a `JSONPointer` object that includes a json path for querying, and returns a `JSONObject` object which has the corresponding path, or throw an error if that path does not exist.
+
+The first one takes in 3 parameters, a `Reader` object which contains some XML input and a `JSONPointer` object that includes a json path for querying, and a `JSONObject` for replacement. And returns a new `JSONObject` object which has the corresponding path replaced with the new given object, or throw an error if that path does not exist.
+
+Both new functions are placed in the `XML.java` file.
+
+The test cases of the functions are placed under the `org.json.junit.milestone2.tests` package, and to run the test case which deals with large file input, first create a folder named `xml_files` under the `/src/test/resources` path, and put the xml files for testing under this path.
+
 # Notes
 
 For more information, please see [NOTES.md](https://github.com/stleary/JSON-java/blob/master/docs/NOTES.md)