How Can I Convert a Java HashMap to a JSON Object?

Converting HashMap to JSON in Java

Converting a HashMap to a JSON object in Java is a straightforward process that can be accomplished using the org.json.JSONObject class. By initializing a new JSONObject object with the HashMap as a parameter, you can seamlessly transform your HashMap into a JSON object representation.

Example:

import org.json.JSONObject;

HashMap<String, String> myHashMap = new HashMap<>();
myHashMap.put("Name", "John Doe");
myHashMap.put("Age", "30");

JSONObject myJsonObject = new JSONObject(myHashMap);

After conversion, the myJsonObject variable will contain the JSON representation of the HashMap, with each key and value pair represented as a JSON object property.

Additional Functions

The org.json.JSONObject class provides a range of useful functions for manipulating JSON data, including:

• get(String key): Retrieves the value associated with the specified key.
• length(): Returns the number of key-value pairs in the object.
• toString(): Converts the object into a JSON string.
• put(String key, Object value): Adds or updates a key-value pair in the object.

Converting JSON Object to JSON String

To convert a JSON object into a JSON string in Java, simply call the toString() method on the JSONObject object. This will return a string representation of the object's data.

Example:

String myJsonString = myJsonObject.toString();

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