TL;DR — As this unresolved 'Cannot be resolved' errors in projects with module-info.java issue reports, vscode is brain dead when it comes to JPMS and module-info.java.
The long-winded version
From my own experience, I can personally vouch for what the reporter of the above-linked vscode issue reports…
„…I've tried both Gradle and Maven…“
…
„…I find that Gradle and Maven will automatically refresh the classpath file and remove my modifications to it, which will bring back the errors…“
…
„…there needs to be module path information set in the classpath file in order for Eclipse to be happy, but there is no good way to do with that from Gradle or Maven…“
Proof that it's a vscode issue is that the exact same project — unchanged except for the removal of your comment — compiles perfectly fine in IntelliJ…
Since your project uses neither Maven nor Gradle — opting instead to use file-based dependency mgt with the jar in the lib folder — you're in even worse shape because you've eliminated the option of applying any JPMS-enabling plugins that could resolve the issue.
For example, by adding the following pom.xml with the appropriate configuration for the maven-compiler-plugin to my experimental version of your project…
…
<dependencies>
<dependency>
<groupId>org.json</groupId>
<artifactId>json</artifactId>
<version>20200518</version>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<configuration>
<source>11</source>
<target>11</target>
<compilerArgs>
<arg>-Xlint:unchecked</arg>
<arg>--add-modules</arg>
<arg>org.json</arg>
</compilerArgs>
</configuration>
</plugin>
</plugins>
</build>
…
…Maven does its magic and processes the module-info.java successfully…
I've successfully resolved other Stackers' JPMS woes by helping them apply that mrJar plugin mentioned in that vscode bug report. So if you're open to using Gradle instead of Maven, I could likewise advise you on how to configure that plugin too.
Answer from deduper on Stack OverflowVideos
I have been trying to figure out this issue forever now but I can't seem to see what I'm doing wrong. I am using VSCode and added the json library (json-20220329.jar) to my referenced libraries. When I add the jar file the errors in my main file go away regarding JSONObject and JSONArray. Everything looks fine until I try running the code and it says that the "package org.json does not exist." I was wondering if anyone knew what could be the problem.
CODE: (App.java)
import java.net.URI;
import java.net.http.HttpClient;
import java.net.http.HttpRequest;
import java.net.http.HttpResponse;
import org.json.JSONObject;
import org.json.JSONArray;
public class App {
public static void main(String[] args) {
HttpClient client = HttpClient.newHttpClient();
HttpRequest request = HttpRequest.newBuilder().uri(URI.create("https://jsonplaceholder.typicode.com/albums")).build();
client.sendAsync(request, HttpResponse.BodyHandlers.ofString())
.thenApply(HttpResponse::body)
.thenAccept(System.out::println)
.join();
}
public static String parse(String responseBody) {
JSONArray albums = new JSONArray(responseBody);
for (int i = 0; i < albums.length(); i++)
{
JSONObject album = albums.getJSONObject(i);
int id = album.getInt("id");
int userID = album.getInt("userId");
String title = album.getString("title");
System.out.println(id + "\t" + title + "\t" + userID);
}
return null;
}
}ERROR:
App.java:8: error: package org.json does not exist
import org.json.JSONObject;
^
App.java:9: error: package org.json does not exist
import org.json.JSONArray;
^
App.java:26: error: cannot find symbol
JSONArray albums = new JSONArray(responseBody);
^
symbol: class JSONArray
location: class App
App.java:26: error: cannot find symbol
JSONArray albums = new JSONArray(responseBody);
^
symbol: class JSONArray
location: class App
App.java:29: error: cannot find symbol
JSONObject album = albums.getJSONObject(i);
^
symbol: class JSONObject
location: class App
5 errorsI'm going to start by saying I'm a complete novice in Java. I've started computer science recently and I've got a project where I have to create a project to represent a server using sockets. The server will has to function as a control a library's book record/register. My professor provided a .json file with the book lists which I have to use.
I tried creating the project on VS Code, but after following these steps:
Downloaded the library from the Maven Repository.
Created a lib folder in your project's root directory and move the json-20230303.jar file to this folder.
My code couldn't import the library and this error appeared every time I tried to use the library:
"src\Gerenciador.java:2: error: package org.json does not exist import org.json.JSONArray;"
After a while I thought it would be easier to import the library on the Ide Eclipse, but after creating the project and adding it via the Build Path option, it still didn't work. Even though the library appeared in the Libraries section in the Java Build Path.
This error: "The type org.json.JSONObject is not accessible" keeps appearing.
I don't know how to fix the problem. I think I'm calling on the library wrong, but I don't know how I should do it. If there is any information missing, let me know and I'll provide it, it's my first time asking for help on a programming forum.
Putting the libraries in your current working directory does not work for Java, you need to add them to the classpath.
If you're using maven, that manages the classpath for you.
If not, you can manage it in VS Code by executing the Java: Configure Classpath command from the Command Palette (Ctrl+Shift+P).
You can add dependencies via Referenced libraries under the JAVA PROJECTS panel.
Or use java.project.referencedLibraries setting in settings.json.
For example:
"java.project.referencedLibraries": [
"library/**/*.jar",
"/home/username/lib/foo.jar"
]
Details can be found in configure-classpath and manage-dependencies.
I ran into a similar issue. The solution was to remove everything from VS Code's workspace storage directory, which was located at $HOME/Library/Application Support/Code/User/workspaceStorage/.
I found this solution here: https://github.com/redhat-developer/vscode-java/wiki/Troubleshooting#clean-the-workspace-directory
Update: This can now be done from within VS Code as of Language Support for Java(TM) by Red Hat Version 0.33.0. Open the command palette and type "java clean" (see official description in link).
As already mentioned previously, you require to clean the project, but that is a bit difficult thing because every folder is a Guid, and you do not know which one to clear, thus requiring you to delete everything. Starting with 0.33.0 version of the plugin you can automatically do that from within the IDE as well, use CTRL + Shift + P and type, java clean, and IDE will show you the suggestion tip for, Java: Clean the Java language server workspace. Upon selection, agree and restart the IDE. It will clean the language server workspace for you.
Another approach can be, the Maven tools within the IDE. If you have this plugin installed, you can use the side bar and utilize the Maven project helper options to perform actions like, clean, install, and package etc. For example, here is the project I am having and the options this shows,
That can be used, graphically, to manage your Maven-based projects. Also, this would work with the Java Extension Pack, not sure yet as to how it would behave with other extensions.
You are missing json-simple-1.1.1.jar from your classpath.
if you are using Maven, add below into your pom.xml.
Copy<dependency>
<groupId>com.googlecode.json-simple</groupId>
<artifactId>json-simple</artifactId>
<version>1.1.1</version>
</dependency>
Or you can download it from here.
Firstly, you don't need the json-simple.jar in your project.
Therefore remove the import org.json.simple.*
Secondly, the best practice is to import only the required classes from your jar.Therefore you can replace import org.json.*; by
Copyimport org.json.JSONArray;
import org.json.JSONException;
import org.json.JSONObject;
import org.json.JSONString;