Eliminating Public Interface

I currently have a BM server that host primarily File sharing and groupwise. I have BM installed on the server and we access groupwise webaccess, SMTP, IMAP and POP via the public interface. I want to eliminate the public interface and route all traffic through our 3rd party firewall and take this server off of the internet. However when I disable the public interface and change the default route none of the services are working. I have narrowed it down to the tcpip filters. What is the best practice for eliminating this interface and making sure all traffic routes through the private interface. I do not have any of the BM modules loaded and really dont use any of the services but I think what happens is traffic comes in through the private but it is still trying to route through the public interface.

This may sound simplistic when you read it, but it really is this
simple. The public interface only gets involved when traffic is sent
to or through it.
Filters are supposed to be applied to the public interface, and not the
private side (unless you've *really* customized them). See tip #13 at
the URL below. (Talking filters here, not exceptions).
If you have changed the default route to an address on the private
side, then packets going to the internet should not touch the public
interface at all. Since you are having a filtering issue, clearly some
things need to be checked out.
1. In filtcfg, check that no filters are applied to the private
interface, and that the filtering action is the default (deny in list,
as seen in tip #13).
2. Check routing table in TCPCON to see what the default route actually
is. Sometimes it's not what you thought you had.
3. Check routers in your network to see if some static NAT or routing
table entry might be pointing to an old public address assigned on the
BMgr server.
4. Use set tcp ip debug=1 (careful! Will see a lot of traffic, and
could crash a production server) to see all IP traffic on the server.
You can then observe packets hitting the public side and maybe see
where they are coming from. PKTSCAN.NLM would be a lot safer to use.
Craig Johnson
Novell Support Connection SysOp
*** For a current patch list, tips, handy files and books on
BorderManager, go to http://www.craigjconsulting.com ***

Similar Messages

Multiple DMVPN instance on the same router one public interface

I know it possible to run multiple instances DMVPN on a router with one public interface.
Question:
If I take one of my site and put it on a different tunnel from all other remote sites will it be able communication to the other site directly? I am running EIGP through the gre Tunnel
example of the hub site:
interface Tunnel100
bandwidth 100000
ip address 192.168.105.254 255.255.255.0
no ip redirects
ip mtu 1400
ip hello-interval eigrp 1 1
ip hold-time eigrp 1 3
no ip next-hop-self eigrp 1
ip nhrp authentication L3GR@RD
ip nhrp map multicast dynamic
ip nhrp map group WAR-881-VPN1 service-policy output SHAPE->20M
ip nhrp map group PLA-2811-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group LIV-2811-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group BRM-2811-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group ELP-2811-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group RAN-2811-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group LAB-2911-VPN1 service-policy output SHAPE->T1(MLPPPx2)
ip nhrp map group ORE-2811-VPN1 service-policy output SHAPE->5M
ip nhrp map group VAU-2811-VPN1 service-policy output SHAPE->10M
ip nhrp map group CAVAURTVP001 service-policy output SHAPE->10M
ip nhrp network-id 100
ip nhrp holdtime 600
ip nhrp max-send 1000 every 10
ip nhrp redirect
ip tcp adjust-mss 1360
no ip split-horizon eigrp 1
ip summary-address eigrp 1 10.87.0.0 255.255.0.0
load-interval 30
delay 100
tunnel source GigabitEthernet0/0
tunnel mode gre multipoint
tunnel key 100
tunnel vrf PUBLIC
tunnel protection ipsec profile IPSEC-DMVPN
interface Tunnel300
bandwidth 100000
ip address 192.168.106.254 255.255.255.0
no ip redirects
ip mtu 1400
ip hello-interval eigrp 1 15
ip hold-time eigrp 1 45
no ip next-hop-self eigrp 1
ip nhrp authentication L3GR@RB
ip nhrp map multicast dynamic
ip nhrp map group CAVAURTVP001 service-policy output SHAPE->10M
ip nhrp network-id 100
ip nhrp holdtime 600
ip nhrp max-send 1000 every 10
ip nhrp redirect
ip tcp adjust-mss 1360
no ip split-horizon eigrp 1
ip summary-address eigrp 1 10.87.0.0 255.255.0.0
load-interval 30
delay 100
tunnel source GigabitEthernet0/0
tunnel mode gre multipoint
tunnel key 100
tunnel vrf PUBLIC
tunnel protection ipsec profile IPSEC-DMVPN
Thanks the help in advance,
Nigel

Hello Mr Manhurt,
I can help you. But first what is EIGP?

Public Interface configuration - Bonding Yes / No ?

Hey, during my setup of my rac, I configured two nics for public usage and two nics for private (interconnect) usage.
While running raccheck utility - it states that no bonding has been configured for public interface.
In a course in oracle university they told us to configure the public interfaces as I did.
Question: Is my configuration incorrect ? Do I need to have a bonding interface for my public network ?
Chris

Please use the SEARCH feature before posting - this is thread# 3 or 4 for this same question.
If you only have 2 NICs it was configured correctly according to your "university", However, your university configuration is WRONG and it is NOT a supported configuration.
See my response to thread: Re: Production site RAC redundant architecture deployment

Non public interfaces

Non public interfaces are not permitted. But I often want to break out the methods of an interface into sub-interfaces for the sake of (at least) comprehensibility. Ultimately, only the aggregate interface is meant to be exposed, but of course, they are all exposed- Java doesn't permit non-public interfaces.
E.G. -
interface Foo extends interface Bar, Baz
class DefaultFoo implements Foo
// implementation of Bar and Baz
of course I could have DefaultFoo just implement Bar and Baz directly, but it's not the point. The point is, I have a good reason
to want these mini-interfaces... for the sake of comprehension. A Foo is just exactly the combination of Bar and Baz
and elsewhere a Goo is an implementation of a Bar and Gaz, where Gaz is some other interface.
So the utility of the interfaces lies in the conceptual cohesion of the abstraction they define, which will never be implemented
individually, but only in different aggregates.
What do other people do with this kind of situation?

Yep, you can do that, but only in classes - no inner interfaces embedded in interfaces, not that that would have helped me in this case !
I think that generally, problems with scoping and issues involving more flexibility around visibility will be addressed in 7.
I knew interfaces can be embedded privately in classes, but not that they could be package protected. Just a feature I never had any reason to use I guess or more likely knew and just forgot!
Sheesh!

Exception Declaration and the Public Interface

What is the connection between a method , exception declaration ( throw ) and public interface. Does every method has an implicit public interface ?? Is list of thrown exceptions, part of a method’s public interface ?

sagararya wrote:
So, how do we know that some method throws an exception that we have to catch?Via the throws clause.
[http://java.sun.com/docs/books/tutorial/essential/exceptions/index.html]
Just as a method must specify what type and how many arguments it accepts and
what is returned, the exceptions that a method can throw must be declared (unless the
exceptions are subclasses of RuntimeException). Also those that are subclasses of Error need not be declared.
The list of thrown exceptions
is part of a method’s public interface.Ah, now I see what you mean. Where did you read that? I don't recall having ever heard the phrase "public interface" used like that.
The above paragraph is from the book, Osborne_Java, written by James Kussow.. Ok.
Can anybody explain me the 4th line in the above paragraph, starting from "The list of thrown exceptions ... "
The list of thrown exceptions is part of a method’s public interface.
The throws keyword is used as follows to list the exceptions that a method can throw:What part do you not understand? Read the tutorial I linked, and if something is still not clear, ask your specific question.
Personally I think the phrase "public interface" is misleading here. If that's what you're hung up on, don't be. It doesn't mean "public" in the sense of Java's "public" access modifier. It just means the list of exceptions is part of what callers of the method know about it.
EDIT: Oops. Too late.
Edited by: jverd on Jun 25, 2008 8:31 AM

IllegalAccessError when trying to create a proxy for a non-public interface

My code proxies a class that extends JDialog. Under Java5 this works fine. However when I switch to Java6 I get a java.lang.IllegalAccessError: class javax.swing.$Proxy3 cannot access its superinterface javax.swing.TransferHandler$HasGetTransferHandler exception.
I went through debugging my code to find out what went wrong. I created the included test code that shows the problem (and because the real codebase is much too big to include here).
package javax.swing;
public class SomePackageInterfaceDefiningClass {
    interface SomeInnerPackageInterface {
package javax.swing;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.Collection;
import org.apache.commons.lang.ArrayUtils;
public class NonPublicInterfaceProxyCreator {
    public static void main(String[] args) {
        // This works fine !
        doTest(WindowConstants.class);
        // This also ! The proxy class package is javax.swing as expected
        doTest(SomePackageInterfaceDefiningClass.SomeInnerPackageInterface.class);
        // JDialog implements the package visible interface
        // javax.swing.TransferHandler.HasGetTransferHandler
        Collection<Class<?>> jdInterfaces = new ArrayList<Class<?>>();
        for (Class<?> interfaze : JDialog.class.getInterfaces()) {
            jdInterfaces.add(interfaze);
        Collection<Class<?>> strippedJdialogInterfaces = new ArrayList<Class<?>>(
                jdInterfaces);
        for (Class<?> interfaze : jdInterfaces) {
            if (interfaze.getName().equalsIgnoreCase(
                    "javax.swing.TransferHandler$HasGetTransferHandler")) {
                strippedJdialogInterfaces.remove(interfaze);
        // Without the package visible interface it works !
        doTest(strippedJdialogInterfaces.toArray(new Class<?>[0]));
        // With the package visible interface it fails
        doTest(jdInterfaces.toArray(new Class<?>[0]));
    private static void doTest(Class... interfaces) {
        // Class clazz = Proxy.getProxyClass(JDialog.class.getClassLoader(),
        // interfaces);
        Class clazz = Proxy.getProxyClass(Thread.currentThread()
                .getContextClassLoader(), interfaces);
        System.out.println("Class created = " + clazz
                + " >>>> Implemented interfaces = "
                + ArrayUtils.toString(clazz.getInterfaces()));
}When I run this code under Java5 I get:
Class created = class $Proxy0 >>>> Implemented interfaces = {interface javax.swing.WindowConstants}
Class created = class javax.swing.$Proxy1 >>>> Implemented interfaces = {interface javax.swing.SomePackageInterfaceDefiningClass$SomeInnerPackageInterface}
Class created = class $Proxy2 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer}
Class created = class $Proxy2 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer}Under Java6 I get:
Class created = class $Proxy0 >>>> Implemented interfaces = {interface javax.swing.WindowConstants}
Class created = class javax.swing.$Proxy1 >>>> Implemented interfaces = {interface javax.swing.SomePackageInterfaceDefiningClass$SomeInnerPackageInterface}
Class created = class $Proxy2 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer}
Exception in thread "main" java.lang.IllegalAccessError: class javax.swing.$Proxy3 cannot access its superinterface javax.swing.TransferHandler$HasGetTransferHandler
     at java.lang.reflect.Proxy.defineClass0(Native Method)
     at java.lang.reflect.Proxy.getProxyClass(Proxy.java:504)
     at javax.swing.NonPublicInterfaceProxyCreator.doTest(NonPublicInterfaceProxyCreator.java:45)
     at javax.swing.NonPublicInterfaceProxyCreator.main(NonPublicInterfaceProxyCreator.java:38)According to the documentation the interface javax.swing.TransferHandler$HasGetTransferHandler should be visible to my class as it is located in the same package, right?
I think there must be some classloading issue when trying to access the non-public interface javax.swing.TransferHandler$HasGetTransferHandler in rt.jar.
I can not figure out what is different between my own non-public interface and Swing's javax.swing.TransferHandler$HasGetTransferHandler.
Any help would be appreciated.

I don't agree completely. What you're telling is true, don't get me wrong. It's the Error that I get from Java that troubles me.
To resolve the classloading question, I changed my code as follows:
package javax.swing;
import java.lang.reflect.Proxy;
import java.util.ArrayList;
import java.util.Collection;
import org.apache.commons.lang.ArrayUtils;
public class NonPublicInterfaceProxyCreator {
    public static void main(String[] args) {
        // This works fine !
        doTest(WindowConstants.class);
        doTest2(WindowConstants.class);
        // This also ! The proxy class package is javax.swing as expected
        doTest(SomePackageInterfaceDefiningClass.SomeInnerPackageInterface.class);
        doTest2(SomePackageInterfaceDefiningClass.SomeInnerPackageInterface.class);
        // JDialog implements the package visible interface
        // javax.swing.TransferHandler.HasGetTransferHandler
        Collection<Class<?>> jdInterfaces = new ArrayList<Class<?>>();
        for (Class<?> interfaze : JDialog.class.getInterfaces()) {
            jdInterfaces.add(interfaze);
        Collection<Class<?>> strippedJdialogInterfaces = new ArrayList<Class<?>>(
                jdInterfaces);
        for (Class<?> interfaze : jdInterfaces) {
            if (interfaze.getName().equalsIgnoreCase(
                    "javax.swing.TransferHandler$HasGetTransferHandler")) {
                strippedJdialogInterfaces.remove(interfaze);
        // Without the package visible interface it works !
        doTest(strippedJdialogInterfaces.toArray(new Class<?>[0]));
        doTest2(strippedJdialogInterfaces.toArray(new Class<?>[0]));
        // With the package visible interface it fails
        doTest(jdInterfaces.toArray(new Class<?>[0]));
        doTest2(jdInterfaces.toArray(new Class<?>[0]));
    private static void doTest(Class... interfaces) {
        ClassLoader contextClassLoader = Thread.currentThread()
                .getContextClassLoader();
        System.out.println("Classloader that creates proxy = " + contextClassLoader);
        try {
            Class clazz = Proxy.getProxyClass(contextClassLoader, interfaces);
            System.out.println("Class created = " + clazz
                    + " >>>> Implemented interfaces = "
                    + ArrayUtils.toString(clazz.getInterfaces()));
        } catch (Throwable e) {
            e.printStackTrace();
    private static void doTest2(Class... interfaces) {
        ClassLoader contextClassLoader = JDialog.class.getClassLoader();
        System.out.println("Classloader that creates proxy = " + contextClassLoader);
        try {
            Class clazz = Proxy.getProxyClass(contextClassLoader, interfaces);
            System.out.println("Class created = " + clazz
                    + " >>>> Implemented interfaces = "
                    + ArrayUtils.toString(clazz.getInterfaces()));
        } catch (Throwable e) {
            e.printStackTrace();
}And here is the result when I run it on Java 1.6:
Classloader that creates proxy = sun.misc.Launcher$AppClassLoader@11b86e7
Class created = class $Proxy0 >>>> Implemented interfaces = {interface javax.swing.WindowConstants}
Classloader that creates proxy = null
Class created = class $Proxy1 >>>> Implemented interfaces = {interface javax.swing.WindowConstants}
Classloader that creates proxy = sun.misc.Launcher$AppClassLoader@11b86e7
Class created = class javax.swing.$Proxy2 >>>> Implemented interfaces = {interface javax.swing.SomePackageInterfaceDefiningClass$SomeInnerPackageInterface}
Classloader that creates proxy = null
java.lang.IllegalArgumentException: interface javax.swing.SomePackageInterfaceDefiningClass$SomeInnerPackageInterface is not visible from class loader
     at java.lang.reflect.Proxy.getProxyClass(Proxy.java:353)
     at javax.swing.NonPublicInterfaceProxyCreator.doTest2(NonPublicInterfaceProxyCreator.java:64)
     at javax.swing.NonPublicInterfaceProxyCreator.main(NonPublicInterfaceProxyCreator.java:18)
Classloader that creates proxy = sun.misc.Launcher$AppClassLoader@11b86e7
Class created = class $Proxy3 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer}
Classloader that creates proxy = null
Class created = class $Proxy4 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer}
Classloader that creates proxy = sun.misc.Launcher$AppClassLoader@11b86e7
java.lang.IllegalAccessError: class javax.swing.$Proxy5 cannot access its superinterface javax.swing.TransferHandler$HasGetTransferHandler
     at java.lang.reflect.Proxy.defineClass0(Native Method)
     at java.lang.reflect.Proxy.getProxyClass(Proxy.java:504)
     at javax.swing.NonPublicInterfaceProxyCreator.doTest(NonPublicInterfaceProxyCreator.java:51)
     at javax.swing.NonPublicInterfaceProxyCreator.main(NonPublicInterfaceProxyCreator.java:41)
Classloader that creates proxy = null
Class created = class javax.swing.$Proxy6 >>>> Implemented interfaces = {interface javax.swing.WindowConstants,interface javax.accessibility.Accessible,interface javax.swing.RootPaneContainer,interface javax.swing.TransferHandler$HasGetTransferHandler}As you can see, I get an IllegalArgumantException telling me that my interface I try to proxy is not visible for JDialog's classloader, as I would expect. Remark that Java tells me that JDialog's classloader is null. Strange, isn't is?
However I get an IllegalAccessError when I try to proxy TransferHandler$HasGetTransferHandler from my own classloader.
Any reason why the error is different?

Public Interface not responding after second node is started in the cluster

Hi
Has anyone ever experienced the public interface not responding between nodes in the cluster (ping, ssh, scp) after the second nodeapps is started in the cluster?
This is a new install so all I have installed so far is the base release of CRS 10.2.0. This is on Solaris10. The vipca failed during the installation, however I was able to proceed and manually add the nodeapps using srvctl add nodeaps -n -o -A.
It seems after the second node is started I loose all connectivity to the public interfaces and to my default gateway.
Also I'm getting the following messages sometimes after I try and stop the nodeapps and start them back up.
CRS-1006: No more members to consider
CRS-0215: Could not start resource 'ora.node1.vip'.
Any suggestions on where I should start troubleshooting?
Thanks

Do you have default GW?
It can connects with GW, can't it?
Check metalink
CRS-0215: Could not start resource 'ora..vip' [ID 356535.1]
CRS-1006: No more members to consider when starting service [ID 465364.1]
Good Luck

2 Public Interfaces and NAT

Hello-
We currently have NW6 running BM3.7 set up with 1 public interface and 1
private interface. Our private interface is 10.1.1.1 and we are NATing
that to our public interface. We are using HTTP proxy services for all our
internet browsing---proxy being the 10.1.1.1 address. The public interface
is on a state WAN link and we are using it for internet browsing, email,
citrix and other state applications. We want to offload our email,
internet and citrix traffic onto another public intrface--which is
provided by a different ISP. I know what I need to do to change over the
email to the new ipaddress on the new interface. How do I set up BM to
route internet traffic to the new public interface? Also how do I make
sure that my citrix traffic is routed to the new interface as well? Any
help with this would be greatly appreciated.
Thanks all in advance!

You cannot arbitrarily send some type of traffic to one NIC, and the
rest to another. The outbound traffic will follow the default route.
You can have some limited control by using static routing to force
traffic to certain addresses out one NIC, but that tends to be useful
mostly with S2S VPN dedicated links.
You can also enable dynamic NAT on the LAN side of one of your internet
routers, and make reply traffic to inbound traffic from that link go
back the way it came in.
Craig Johnson
Novell Support Connection SysOp
*** For a current patch list, tips, handy files and books on
BorderManager, go to http://www.craigjconsulting.com ***

Possibility of adding the 3rd interface as a 2nd Public interface?

Is it possible, with VPN 3030, to configure the 3rd interface (which is labeled as "External" and, is usually used for "management", I assume) as another Public interface? So that two different kinds of VPN connections can be physically separated....
Any help and pointers will be much appreciated! -Bill

Hi Aamir,
I am having problem to understand the use of External interface of VPN3000.
Does it mean I can have a VPN3000 with two Providers? Public interface terminates to ISP 1 and External interface terminates to ISP 2 ?
Regarding the routing (only one default gateway) does it mean the following traffic flow ?
1. Incoming traffic from ISP 1 will go to the Public interface and outgoing traffic will go through the same Public interface.
1. Incoming traffic from ISP 2 will go to the External interface , but outgoing traffic will go through Public interface.
Thanks,
Engel

Changing Public Interface on Clusterware

Hi,
I have a 4 RAC node 10.2.0.3 running on RedHat Linux AS 3. Recently I am noticing that eth0 on one of the nodes starts going up and down for short periods of time. If this goes long enough it affects connections being established to it etc.
I am fearing that the nic card is about to fail since this hardware is fairly old. The machine has 2 other unused nic cards on it and I want to change the public interface the clusterware uses to one of these ex eth2.
I know that the procedure to do is, is using oifcfg, but my question is. If I change the interface on node 4 ex $ORA_CRS_HOME/bin/oifcfg setif -global eth2/192.168.1.0:public, would this mean that public interface uses eth2 only for node 4 or for the other 3 as well. Just to be clear I would like the other 3 nodes to still use their current public interface ie eth0.
Thanks in advance.

You need to have the same interface name on all the nodes for public. So you could ensure that the other card on node 4 becomes eth0.
Regards,
Anil Nair
Global Technical Lead/ Oracle Clusterware and RAC
Oracle Support.

Is it possible to allow ICMP ping responce on the public interface for WRT54G?

Hi I need to remotely monitor a WRT45G from a remote host on the Internet. As such, I want to allow ICMP ping replies on the public Internet interface. However, I have found no feature to allow me to do this. Similar Netgear devices do allow this feature. I suspect the answer is, "you can't do that".

Yes this is possible. I just managed it on a WRT54GL.
On the routers default configuration page: 192.168.1.1 (or whatever you set it to) select the Security-tab, click sub-tab Firewall, uncheck the box next to "Block Anonymous Internet Requests", save settings. - I guess there's a risk involved, but it works.

Public Interface

Hi all!
I'm trying to access a WebDynPro App from another WebDynPro App, like here is explained:
https://www.sdn.sap.com/irj/servlet/prt/portal/prtroot/docs/library/uuid/91b6ad90-0201-0010-efa3-9626d2685b6e
But I have some problems, cause when I create an Exit Outbound Plug, the IPublic interface is not created.¿Am I forgetting something?
Thank you in advance!

hi Eneko..,
I Think you would not have added the required controller to your list.
go to the view properties->required controllers and add the required interface or component controller to your view..then u could get the interface generated..
check it out..

Metadata for Session EJB whose public interface extends EJBLocalHome?

I would like to get meta data information for a local Session EJB implemented using
EJBLocalHome and EJBLocalObject instead of EJBHome and EJBObject respectively.
1. Is this possible, since EJBLocalHome do not define the method getEJBMetaData()
that EJBHome does?
2. Is there a way to get the meta data information for such local EJBs in WebLogic
using any other mechanism?
Thanks in advance & Regards,
Sudhrity

Hi Sitaro,
Please refer to the following links... you will get information about how to lookup Local EJB3...
http://jaysensharma.wordpress.com/ejbs_weblogic/
http://jaysensharma.wordpress.com/2009/08/16/weblogic-10-3-ejb3-local-lookup-sample/
Here you will get the information of Customizing The JNDI name and to look them up.
Thanks
Jay SenSharma
http://jaysensharma.wordpress.com/ (WebLogic Wonders Are Here)

Adding Pix device public interface through Proxy server into CSM Fails

Hi
I am trying to add a device into CSM. The device is only reachable through proxy server. If i try to add the device, the connectivity test fails" unable to communicate with device". If i debug on the PIX i see no connection attemps. If imake a https connection from the Explorer from the windows server running CSM i get connected. I have set the proxy settings under Server Administration. I can update packages from CCO through the proxy. Is there somewhere else to tell CSM to run through proxy ?

Hello,
maybe your problem has to do something with loading SLPDA.NLM. If you
cannot get to open Autoexec.ncf then go back to DOS-Mode, rename this
file in C:\nwserver-directory and start again. i have seenthis behaviour
on servers loading SLPDA with no network-communication and they stop
loading at WPSD.NLM. Try to load SLPD.NLM manually when the server is
up. After that shift the line in Autoexec.ncf where you want to load
Slpda.NLM to the end of the file and boot the server again to see what
happens.
Good luck
Burkhard Wiegand
Netware Admin
Debeka-Versicherungen
D-56068 Koblenz

Why only public methods in interfaces?

Howdy all,
I'm wondering if someone can shed some light on why Java doesn't allow interfaces to declare non-public methods.
Ideally, I'd like to do something like this:
public Interface Foo {
protected void setFooProperty(int);
public int getFooProperty();
public Interface Goo {
protected void makeGooey(boolean);
public boolean isGooey();
public class A implements Foo
public class B implements Goo
public class C implements Foo, GooI don't see any technical reason why interfaces must be restricted to declaring public methods only, but it seems too arbitrary to have been done without reason. Any ideas?

I don't think that is a good idea to put non-public methods in public interfaces. But I beleive that's a good idea to have protected (or friendly) interfaces to be used only in package scope. It could help a lot some projets defining a second level of data exposure of an object so that developers of that package could have more information that others users from outside the package have that are interesting to develop better algorithm that work with that data. In this way, we can defien thre levels of that access: The lower is the package user, that can see the minimum that's possible, above him we have the package developer that don't work directly with the data, but needs some deep access to it to do cool stuff, and finally we have the guy that is doing the object that deals directly with the data (and encapsulate it).
In this way we can decouple a little the data from the algorithms that work on it, put between them an interface that standarize the access to the data in an intermediate level.
Hope you are able to understand what I wrote (my english isn't so good!).
RGB

Eliminating Public Interface

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