JRE 8 rt.jar is the JAR file for JRE 8 RT (Runtime) libraries. JRE (Java Runtime) 8 is the runtime environment included in JDK 8. JRE 8 rt.jar libraries are divided into 6 packages:

com.* - Internal Oracle and Sun Microsystems libraries
java.* - Standard Java API libraries.
javax.* - Extended Java API libraries.
jdk.* -  JDK supporting libraries.
org.* - Third party libraries.
sun.* - Old libraries developed by Sun Microsystems.

JAR File Information:

Directory of C:\fyicenter\jdk-1.8.0_191\jre\lib
      63,596,151 rt.jar

Here is the list of Java classes of the javax.* package in JRE 1.8.0_191 rt.jar. Java source codes are also provided.

⏎ javax/management/remote/rmi/RMIServerImpl_Stub.java

// Stub class generated by rmic, do not edit.
// Contents subject to change without notice.

package javax.management.remote.rmi;

public final class RMIServerImpl_Stub
    extends java.rmi.server.RemoteStub
    implements javax.management.remote.rmi.RMIServer
{
    private static final long serialVersionUID = 2;
    
    private static java.lang.reflect.Method $method_getVersion_0;
    private static java.lang.reflect.Method $method_newClient_1;
    
    static {
	try {
	    $method_getVersion_0 = javax.management.remote.rmi.RMIServer.class.getMethod("getVersion", new java.lang.Class[] {});
	    $method_newClient_1 = javax.management.remote.rmi.RMIServer.class.getMethod("newClient", new java.lang.Class[] {java.lang.Object.class});
	} catch (java.lang.NoSuchMethodException e) {
	    throw new java.lang.NoSuchMethodError(
		"stub class initialization failed");
	}
    }
    
    // constructors
    public RMIServerImpl_Stub(java.rmi.server.RemoteRef ref) {
	super(ref);
    }
    
    // methods from remote interfaces
    
    // implementation of getVersion()
    public java.lang.String getVersion()
	throws java.rmi.RemoteException
    {
	try {
	    Object $result = ref.invoke(this, $method_getVersion_0, null, -8081107751519807347L);
	    return ((java.lang.String) $result);
	} catch (java.lang.RuntimeException e) {
	    throw e;
	} catch (java.rmi.RemoteException e) {
	    throw e;
	} catch (java.lang.Exception e) {
	    throw new java.rmi.UnexpectedException("undeclared checked exception", e);
	}
    }
    
    // implementation of newClient(Object)
    public javax.management.remote.rmi.RMIConnection newClient(java.lang.Object $param_Object_1)
	throws java.io.IOException
    {
	try {
	    Object $result = ref.invoke(this, $method_newClient_1, new java.lang.Object[] {$param_Object_1}, -1089742558549201240L);
	    return ((javax.management.remote.rmi.RMIConnection) $result);
	} catch (java.lang.RuntimeException e) {
	    throw e;
	} catch (java.io.IOException e) {
	    throw e;
	} catch (java.lang.Exception e) {
	    throw new java.rmi.UnexpectedException("undeclared checked exception", e);
	}
    }
}

⏎ javax/management/remote/rmi/RMIServerImpl_Stub.java

Or download all of them as a single archive file:

File name: jre-rt-javax-1.8.0_191-src.zip
File size: 5381005 bytes
Release date: 2018-10-28
Download 

⇒ JRE 8 rt.jar - org.* Package Source Code

⇐ JRE 8 rt.jar - java.* Package Source Code

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