Java here is the main language of the repository. Java compiles to bytecode for the Java VM, so running the software needs a Java runtime, and extensions or plugins for it are usually written in Java and packaged as JAR files. A record carries this value when Java makes up most of the codebase, as stated by the project or shown by its repository. Keycloak and Spring Boot are examples.
24 projects are written in Java, listed alphabetically. Mostly web frameworks, content management systems and APIs and backends, of 11 categories in all. 38 records do not record this field, and cannot appear here either way. Counts only projects with momentum; the full list has the rest.
A
Ametys CMSJava content management system for websites, intranets and portals, published under the Apache License.
Apache OFBizJava suite of enterprise business applications for ERP, CRM and e-commerce, built on an entity engine, a service engine and a widget-based UI.
Apache ShenYuJava-native API gateway for HTTP, Dubbo, gRPC and WebSocket services, with plugins for authentication, traffic control and observability.
- Apache SkyWalking
Application performance monitoring system for distributed systems, microservices and container-based architectures.
- Apache Struts
Apache Struts is an open-source MVC framework for building Java web applications.
- Apache Tomcat
Java servlet and JSP container, an open source implementation of the Jakarta Servlet, Pages, Expression Language, WebSocket, Annotations and Authentication specifications.
- Apache Wicket
Component-based Java web framework that keeps behavior in Java classes and markup in plain HTML.
D
E
- Eclipse Mojarra
Eclipse's implementation of the Jakarta Faces specification for building Java web user interfaces.
F
FessJava enterprise search server with a built-in crawler, an admin console and a search UI, built on OpenSearch.
K
M
N
O
Oracle ADFJava EE application framework from Oracle for building enterprise applications in JDeveloper and running them on an application server with the ADF runtime installed.
Q
QuarkusJava framework for building cloud-native applications that run on the JVM or as native executables.
S
- S3Proxy
Java server that speaks the S3 API and forwards requests to other object storage backends, such as AWS S3, Azure Blob Storage, Google Cloud Storage, the local filesystem and SFTP.
Spring BootJava framework for building stand-alone Spring applications with an embedded web server and auto-configuration.
Spring FrameworkComprehensive programming and configuration model for Java-based enterprise applications, on any deployment platform.
SuperTokensOpen source user authentication server, Core, with frontend and backend SDKs, self-hosted or as a managed cloud service.
W
- WaveMaker
Low-code platform for building web and hybrid mobile applications, offered as a cloud service and as an on-premise installation.
What is the best web software written in Java?
We can't tell from here. What suits an editor-heavy marketing site can be wrong for a static documentation site. The list is alphabetical and nobody paid for a place on it.




