I need to extract two pieces of information about two IP addresses and then write those information plus two addresses.
I was thinking of a Set of Pairs for IP addresses, but by which data structure I can write all these information?
Thanks
PcapPacketHandler<String> jPacketHandler = new PcapPacketHandler<String>(){
int totalLength = 0;
public void nextPacket(PcapPacket packet, String user) {
Ip4 ip = new Ip4();
String sIP;
String dIP;
if (packet.hasHeader(ip) == false){
return;
}
totalLength = totalLength+ ip.getPayloadLength();
sIP = org.jnetpcap.packet.format.FormatUtils.ip(ip.source());
dIP = org.jnetpcap.packet.format.FormatUtils.ip(ip.destination());
System.out.println("SIP = "+sIP+" "+"destIP = "+dIP+" "+"Payload Length = "+ip.getPayloadLength());
System.out.println("Total Length = "+totalLength);
}
};
pcap.loop(10, jPacketHandler, "");
pcap.close();
Even though this isn't a Javascript app, you could use JSON as it provides a concise way to read/store multiple pieces of data together. Check out the JSON Java Documentation for details about classes, and to download the related source.
If you're just writing the information you could always use a Hashmap. Unless you know what you're planning to do with the data, it's hard to say what's best.
Just make a custom class (POJO), and depending on how you want to write it make it Serializable. That way you can clearly name your fields (and getters and setters) making your code easier to read (and extend).
some thing like this...
class BigClass { //<br>
private IPAdreess addr1; //<br>
private IPAddress addr2; //<br>
private SomeInfo additionalInfo;//<br>
//implement accessors//<br>
//implement equals, hashCode//<br>
}//<br>
IPAddress, SomeInfo are your user types. In java, InetAddress represents IP address. This may be much more than your custom type.
The selection of suitable data structure of "set" could be decided many factors.. Do you want to retain the order? Do you populate it via multiple threads? How many entries you expect in the set? 100s? A million?
Why not post your code? It may be easier to give feedback with real code..
I don't quite understand what graph you exactly want to plot. What I would do is
Dump all data into an sql database
Run a query to produce input for your chart.
Plot the chart e.g. with JFreeChart or even Excel
I imagine a query along the line
select source_ip, dest_ip, sum(time), sum(sent_bytes) group by source_ip, dest_ip
Related
I use Apache Thrift protocol for tablet-server and interlanguage integration, and all is OK few years.
Integration is between languages (C#/C++/PC Java/Dalvik Java) and thrift is probably one of simplest and safest. So I want pack-repack sophisticated data structures (and changed over years) with Thrift library. Lets say in thrift terms kind of OfflineTransport or OfflineProtocol.
Scenario:
I want to make backup solution, for example during internet provider failure process data in offline mode: serialise, store, try to process in few ways. For example sent serialised data by normal email via poor backup connection etc.
Question is: where in Thrift philosophy is best extension point for me?
I understand, only part of online protocol is possible to backup offline, ie real time return of value is not possible, that is OK.
Look for serializer. There are misc. implementations but they all share the same common concept to use a buffer or file / stream as transport medium:
Writing data in C#
E.g. we plan to store the bits into a bytes[] buffer. So one could write:
var trans = new TMemoryBuffer();
var prot = new TCompactProtocol( trans);
var instance = GetMeSomeDataInstanceToSerialize();
instance.Write(prot);
Now we can get a hold of the data:
var data = trans.GetBuffer();
Reading data in C#
Reading works similar, except that you need to know from somewhere what root instance to construct:
var trans = new TMemoryBuffer( serializedBytes);
var prot = new TCompactProtocol( trans);
var instance = new MyCoolClass();
instance.Read(prot);
Additional Tweaks
One solution to the chicken-egg problem during load could be to use a union as an extra serialization container:
union GenericFileDataContainer {
1 : MyCoolClass coolclass;
2 : FooBar foobar
// more to come later
}
By always using this container as the root instance during serialization it is easy to add more classes w/o breaking compatibility and there is no need to know up front what exactly is in a file - you just read it and check what element is set in the union.
There is an RPC framework that uses the standard thrift Protocol named "thrifty", and it is the same effect as using thrift IDL to define the service, that is, thrify can be compatible with code that uses thrift IDL, which is very helpful for cross-platform. And has a ThriftSerializer class in it:
[ThriftStruct]
public class LogEntry
{
[ThriftConstructor]
public LogEntry([ThriftField(1)]String category, [ThriftField(2)]String message)
{
this.Category = category;
this.Message = message;
}
[ThriftField(1)]
public String Category { get; }
[ThriftField(2)]
public String Message { get; }
}
ThriftSerializer s = new ThriftSerializer(ThriftSerializer.SerializeProtocol.Binary);
byte[] s = s.Serialize<LogEntry>();
s.Deserialize<LogEntry>(s);
you can try it:https://github.com/endink/Thrifty
I'm trying to create an SNMP4j agent and am finding it difficult to understand the process correctly. I have successfully created an agent that can be queried from the command line using snmpwalk. What I am having difficulty with is understanding how I am meant to update the values stored in my implemented MIB.
The following shows the relevant code I use for creating the MIB (I implement Host-Resources-MIB)
agent = new Agent("0.0.0.0/" + port);
agent.start();
agent.unregisterManagedObject(agent.getSnmpv2MIB());
modules = new Modules(DefaultMOFactory.getInstance());
HrSWRunEntryRow thisRow = modules.getHostResourcesMib().getHrSWRunEntry()
.createRow(oidHrSWRunEntry);
final OID ashEnterpriseMIB = new OID(".1.3.6.1.4.1.49266.0");
thisRow.setHrSWRunIndex(new Integer32(1));
thisRow.setHrSWRunName(new OctetString("RunnableAgent"));
thisRow.setHrSWRunID(ashEnterpriseMIB);
thisRow.setHrSWRunPath(new OctetString("All is good in the world")); // Max 128 characters
thisRow.setHrSWRunParameters(new OctetString("Everything is working")); // Max 128 characters
thisRow.setHrSWRunType(new Integer32(HrSWRunTypeEnum.application));
thisRow.setHrSWRunStatus(new Integer32(HrSWRunStatusEnum.running));
modules.getHostResourcesMib().getHrSWRunEntry().addRow(thisRow);
agent.registerManagedObject(modules.getHostResourcesMib());
This appears to be sufficient to create a runnable agent. What I do not understand is how I am meant to change the values stored in the MIB (how do I, for example, change the value of HrSWRunStatus). There seem to be a few kludge ways but they don't seem to fit with the way the library is written.
I have come across numerous references to using/overriding the methods
prepare
commit
undo
cleanup
But cannot find any examples where this is done. Any help would be gratefully received.
In protected void registerManagedObjects(), you need to do something like new MOMutableColumn(columnId, SMIConstants.SYNTAX_INTEGER, MOAccessImpl.ACCESS_READ_WRITE, null); for your HrSWRunStatus. Take a look at the TestAgent.java example of SNMP4J-agent source.
I need a Fake Data Generator (e.g., For a person's personal information like first name, last name, email and all) for console based jdbc application.
Because I want to add those data of random person to MySQL database.
My code for MySQL as below :
String url1 = "jdbc:mysql://localhost:3306/restaurant";
String user = "root";
String password = "root";
conn1 = DriverManager.getConnection(url1, user, password);
if (conn1 != null) {
System.out.println("Connected to the database restaurant");
// I want add data generator here.
}
You have DataFactory. It generated names (even some specific region names), addresses, birth dates or other dates, general random strings, you can even give it some arrays of random stuff to generate from, etc
Edit: usage example
In order to get different output each time, create it with your seed for Random(). The best seed is nano time:
DataFactory df1 = DataFactory.create(System.nanoTime());
Everytime you create it, you will get different output.
You can use jFairy. This will best suited for you.
The github link for a project : https://github.com/Codearte/jfairy/tree/master/src/main
Code Example:
Fairy fairy = Fairy.create();
Person person = fairy.person();
System.out.println(person.fullName());
You can checkout randomizer for random data generation.This library helps to create random data from given Model class.Checkout below example code.
public class Person {
#FirstName
String mFirstName;
#LastName
String mLastName;
#Email
String mEmailId;
}
//Generate random 100 Person(Model Class) object
Generator<Person> generator = new Generator<>(Person.class);
List<Person> persons = generator.generate(100);
As there are many built in data generator is accessible using annotation,You also can build custom data generator.I suggest you to go through documentation provided on library page.
You can use dummycreator library for generating dummy objects dummycreator.
It can be used like this
public static <T> T create(final Class<T> clazz) {
return dummyCreator.create(clazz);
}
More, you can specify bindings for specifying how to generate some classes.
static {
bindings.add(String.class, new RandomStringFactory());
bindings.add(Examination.class, new RandomExaminationFactory());
}
I've recently authored a library called MockNeat. It allows you to bootstrap data generation.
On the wiki page there is detailed tutorial on how you can programatically generate SQL Inserts for your application.
In the gameserver & client that I'm planning to make, I'm gonna have a lot of packets in the long run that I have to handle. I'm wondering what are the best-practices on how to handle my different packets.
My packets payload will start with a PacketID.
Would it be a good idea to create a seperate class extending Packet and handle the logics there? For example Packet001Login? This will give me a lot of classes in the long run.
Is it better to make a gigantic switch statement? I doubt it.
Is the best way something that I didn't think of?
Any advice is greatly appreciated.
If you do have enougth calculation time on the server side you should work on a technique to create prototypes for different package types.
To illustrate the point and the idea of this i give you some UML like class descriptions
UML:
class PacketPrototype
+ PacketPrototype(PacketType)
+ addData(DataType, Bitlength, ...)
+ deserilize(Bitstream stream) : ReceivedPacket
+ serilizeThis() : ToSendPacket
+ getPacketType() : int
you need also a class which have all PacketPrototypes and decides on the Type of each PacketPrototype object which Prototype should be used to deserilize the data.
you need one class which knows every PacketPrototype, i call it PacketPrototypeHolder
class PacketPrototypeHolder
+ register(PacketPrototype)
+ getPrototypeForPacketType(int Type) : PacketPrototype
The Protocol on setup time is as follows
PacketEnemy00 = new PacketPrototype(0)
PacketEnemy00.addData(Types.Int, 5) // health
PacketEnemy00.addData(Types.String, 16) // name
...
this means that a packet of type 0 consists out of a int which is 5 bits long and a string which does have a maximal length of 16 characters.
We have to add the PacketPrototype after setup to our PacketPrototypeHolder
PacketHolder.register(PacketEnemy00)
If the server or client receives something we read the type of the packet, then we do
(you can read the data from Bitstream)
Type = Bitstream.readInt(5)
Prototype = PacketHolder.getPrototypeForPacketType(Type)
ReceivedPacket OfReceivedPacket = Prototype.deserilize(Bitstream)
// we need here a switch/if statement to determine how to handle the reading of the data
switch(Type)
{
case 0: // PacketEnemy00
the Prototype.deserilize call reads the data from the datastream and puts it into a ReceivedPacket Object, from there you can access your data either with index operations or with named access.
As an example i do it with indices
int UnitHealth = OfReceivedPacket.getInt(/* index, we want the 1st int */0);
string UnitName = OfReceivedPacket.getString(/* index, we want the 1st string */0);
and so on...
break;
...
}
So effectivly i moved the switch statement from inside the network layer to the application/usage layer.
To remove the switch you need a data driven approach. But its in the engine more complicated to realize than the hardcoded approach.
I am working on refactoring an existing application written in PowerBuilder and Java and which runs on Sybase EA Server (Jaguar). I am building a small framework to wrap around Jaguar API functions that are available in EA Server. One of the classes is to get runtime statistics from EA Server using the Monitoring class.
Without going into too much detail, Monitoring is a class in EA Server API that provides Jaguar Runtime Monitoring statistics (actual classes are in C++; EA Server provides a wrapper for these in Java, so they can be accessed through CORBA).
Below is the simplified version of my class. (I made a superclass which I inherit from for getting stats for components, conn. caches, HTTP etc).
public class JagMonCompStats {
...
public void dumpStats(String type, String entity) {
private String type = "Component";
private String entity = "web_business_rules";
private String[] header = {"Active", "Pooled", "invoke"};
// This has a lot more keys, simplified for this discussion
private static short[] compKeys = {
(short) (MONITOR_COMPONENT_ACTIVE.value),
(short) (MONITOR_COMPONENT_POOLED.value),
(short) (MONITOR_COMPONENT_INVOKE.value)
};
private double[] data = null;
...
/* Call to Jaguar API */
Monitoring jm = MonitoringHelper.narrow(session.create("Jaguar/Monitoring"));
data = jm.monitor(type, entity, keys);
...
printStats(entity, header, data);
...
}
protected void printStats(String entityName, String[] header, double[] data) {
/* print the header and print data in a formatted way */
}
}
The line data = jm.monitor is the call to Jaguar API. It takes the type of the entity, the name of the entity, and the keys of the stats we want. This method returns a double array. I go on to print the header and data in a formatted output.
The program works, but I would like to get experts' opinion on OO design aspect. For one, I want to be able to customize printStats to be able to print in different formats (for e.g., full blown report or a one-liner). Apart from this, I am also thinking of showing the stats on a web page or PowerBuilder screen, in which case printStats may not even be relevant. How would you do this in a real OO way?
Well, it's quite simple. Don't print stats from this class. Return them. And let the caller decide how the returned stats should be displayed.
Now that you can get stats, you can create a OneLinerStatsPrinter, a DetailedStatsPrinter, an HtmlStatsFormatter, or whatever you want.