java list to json string

stackoverflow.com › questions › 14228912 › how-to-convert-list-to-json-in-java

Use GSON library for that. Here is the sample code

List<String> foo = new ArrayList<String>();
foo.add("A");
foo.add("B");
foo.add("C");

String json = new Gson().toJson(foo );

Here is the maven dependency for Gson

<dependencies>
    <!--  Gson: Java to Json conversion -->
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.2.2</version>
        <scope>compile</scope>
    </dependency>
</dependencies>

Or you can directly download jar from here and put it in your class path

http://code.google.com/p/google-gson/downloads/detail?name=gson-1.0.jar&can=4&q=

To send Json to client you can use spring or in simple servlet add this code

response.getWriter().write(json);

Answer from code_fish on Stack Overflow

Baeldung

baeldung.com › home › java › java list › converting a java list to a json array

Converting a Java List to a Json Array | Baeldung

June 18, 2025 - Furthermore, web services and APIs often rely on JSON format to provide public data in a standardized manner. Its versatility makes it compatible with modern programming languages, allowing seamless integration across different platforms and technologies. In this scenario, let’s consider a Java list named “articles” that contains elements as follows: public List<String> list = Arrays.asList("Article 1", "Article 2", "Article 3"); public String expectedJsonArray = "[\"Article 1\",\"Article 2\",\"Article 3\"]";

Stack Overflow

stackoverflow.com › questions › 14228912 › how-to-convert-list-to-json-in-java

How to convert List to Json in Java - Stack Overflow

Top answer

1 of 8

153

Use GSON library for that. Here is the sample code

List<String> foo = new ArrayList<String>();
foo.add("A");
foo.add("B");
foo.add("C");

String json = new Gson().toJson(foo );

Here is the maven dependency for Gson

<dependencies>
    <!--  Gson: Java to Json conversion -->
    <dependency>
        <groupId>com.google.code.gson</groupId>
        <artifactId>gson</artifactId>
        <version>2.2.2</version>
        <scope>compile</scope>
    </dependency>
</dependencies>

Or you can directly download jar from here and put it in your class path

http://code.google.com/p/google-gson/downloads/detail?name=gson-1.0.jar&can=4&q=

To send Json to client you can use spring or in simple servlet add this code

response.getWriter().write(json);

2 of 8

You need an external library for this.

JSONArray jsonA = JSONArray.fromObject(mybeanList);
System.out.println(jsonA);

Google GSON is one of such libraries

You can also take a look here for examples on converting Java object collection to JSON string.

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