A UML Diagram for Java is a static structure diagram that depicts the structure of a system by displaying the system's classes, attributes, operations (or methods), and object relationships. As an object-oriented notation, UML is an excellent choice for any project that uses Java as its implementation language. Java was created from the ground up with the object plumbing required to benefit from UML model design elements. In a UML diagram Java, classes Java classes in the source code correspond to Java classes. The diagram showcases the names and attributes of the classes and their connections and, in some cases, their methods.