gmane.comp.java.xstream.user

Re: Conversion Exception

Lucas Eskopinski — 2008-12-02T01:27:37

Hi, I created a class "IntegerConverter implements Converter" with the method: < at >Override public Object unmarshal(HierarchicalStreamReader reader, UnmarshallingContext arg1) { System.out.println("unmarshal!"); if ((reader.getValue() != null) && (!reader.getValue().equals(""))) { return Integer.parseInt(reader.getValue()); } else { return null; } } how could I write marshal method for writing the attribute without value? < at >Override public void marshal(Object obj, HierarchicalStreamWriter writer, MarshallingContext context) { //???? } Thanks. Lucas Vargas Eskopinski. Mark Waschkowski wrote:

Re: Conversion Exception

Mark Waschkowski — 2008-12-02T00:42:29

OK, if you have special needs, then you will have to create a custom converter, see: http://xstream.codehaus.org/converter-tutorial.html Its fairly straightforward, and when you are unmarshalling you can just write some code to ignore empty strings. Cheers, Mark On Mon, Dec 1, 2008 at 5:44 PM, Lucas Eskopinski public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: Conversion Exception

Lucas Eskopinski — 2008-12-01T22:44:46

Hi Mark, Thanks for your response. Yes, the XStream not generate attributes with null value, but I need. Is there any sample this type converter to null values? Thanks. Lucas Vargas Eskopinski. Mark Waschkowski wrote:

RE: Custom Mapper

Jörg Schaible — 2008-12-01T20:53:05

Hi Calvin, Wu, Calvin (Technology) wrote: OK, that's one of the "general" reasons ;-) Have a look at the CustomMapperTest in the com.thoughtworks.acceptance package. This acceptance test already has such an implementation. - Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: Issue implementing Serializable interface

Jörg Schaible — 2008-12-01T20:50:01

Hi Mark, Mark Codere wrote: XStream uses different kind of converters for different type of objects. You can write converters yourself or rely on the ones that are delivered by XStream and registered by default. Those are documented here: http://xstream.codehaus.org/converters.html. XStream really tries hard to recreated any object (graph) that has been written with XStream before. I emphasis on this sequence, since each converter is free in its implementation what it writes into the XML for the object it is handling. Your description now seems to imply that you try to read XML that has *not* been generated by XStream. While you can tweak XStream to some extend it is sometimes necessary to implement an own converter. In general follow the advice of the FAQ: http://xstream.codehaus.org/faq.html#XML_unmarshalling_fails. In any case it is always useful to see the XML that is generated and the XML that should be generated (or read). Regards, Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: How to use XSTream to persist a Graph Object??

Mark Waschkowski — 2008-12-01T18:10:19

Hi, Actually, your problem is *not* with XStream, its with how you setup your object model. A lot could be said about this, but the simple answer is: Note the following method: getSlider it takes parameters: String title, String name, int min, int max, int value, int minorSpace, int majorSpace What you could do is persist the default parameters somewhere and then read them in and call the getSlider method with those parameters. You could use a properties file for example. However...you have chosen XStream for serialization, so what you should then do is create an object called SliderProperties and create an attribute for each of the above parameters. Then, create a default SliderProperties object, serialize it with XStream and store the resulting XML with your project. As well, create a new method with the following signature: getSlider(SliderProperties sliderProperties) The method will do the same thing the current code does now, but calling on the SliderProperties object for all the needed state. Now, when your project loads, have it read in the stored (at this point, default) XML and initialize the system using the new method. Then, during execution, when the user changes some value, update the SliderProperties object and then serialize the changes using XStream and store the xml file. Then, the next time your system loads it will always have the latest state to load back from. Just to reiterate, this is not an XStream issue, this is an application design issue. Regards, Mark On Mon, Dec 1, 2008 at 12:22 PM, sunnymanman public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: RV: Arraylist

Mark Waschkowski — 2008-12-01T17:53:52

This is accomplished via: http://xstream.codehaus.org/manual-tweaking-output.html (see section on implicit collections and give it a try with an Array or a List). Regards, Mark On Mon, Dec 1, 2008 at 12:13 PM, Alejandro Vergara public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: Conversion Exception

Mark Waschkowski — 2008-12-01T17:51:03

Yes, I know. I'm not responding to your issue as I don't currently have the time nor in depth experience doing XStream support to easily provide you with an answer. Please don't post into two threads at once, and might I suggest that you wait patiently for someone to answer your question? Regards, Mark On Mon, Dec 1, 2008 at 12:08 PM, Mark Codere public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

RE: Custom Mapper

Wu, Calvin (Technology — 2008-12-01T17:33:37

For example, removing underscore of field names. Calvin -----Original Message----- From: Jörg Schaible [mailto:Joerg.Schaible-ysaFb9yBoMtWk0Htik3J/w< at >public.gmane.org] Sent: Friday, November 28, 2008 7:11 AM To: user-wQG/9G7OwhzIJWOP8RzEEmD2FQJk+8+b< at >public.gmane.org Subject: RE: [xstream-user] Custom Mapper Hi Calvin, Wu, Calvin (Technology) wrote on Friday, November 28, 2008 12:51 PM: Mappers and converters are fundamental different things. Since your question imply some lack of understanding (no offence, we do *not* encourage own mappers in first place - it is more like last resort), I'd like to know first, why you think you need a custom mapper? - Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Re: How to use XSTream to persist a Graph Object??

sunnymanman — 2008-12-01T17:22:37

Thanks Mark: But I am very new to XStream, really did not know how to do it, can you help throw some lights here to guide how to apply XStream to my example?? I can run simple case in XStream tutorial, but I am confused with this example. Thanks Mark Waschkowski wrote:

RV: Arraylist

Alejandro Vergara — 2008-12-01T17:13:28

Hi all, I need map this estruct: cad w/o fees susp late badck other corp try with data type arraylist but no work! can any body help me? Thanks Alejandro.

Re: Conversion Exception

Mark Codere — 2008-12-01T17:08:23

Hi Mark, I didn't write the email to which you responded - that was someone else. Here's my issue: I am using XStream to deserialize an object from XML and I keep getting the following fail message: com.thoughtworks.xstream.converters.ConversionException: Cannot deserialize object with new readObject()/writeObject() methods ---- Debugging information ---- class : com.Request required-type : com.Request path : /work_request line number : 1 ------------------------------- at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doUnmarshal(SerializableConverter.java:270) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:150) at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:81) at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:55) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:75) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:59) at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:142) at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:33) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:931) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:917) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:861) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:853) After much digging through XStream source code, it appears that the java object I'm trying to deserialize from the XML is not being created because it's an instance of a class that implements the Serializable interface. It seems as though, a SerializableConverter is being used as opposed to the AbstractReflectionConverter. In the DefaultConverterLookup.lookupConverterForType(), the SerializableConverter is found since it's isSerializable() returns true after passing the serializationMethodInvoker.supportsReadObject() test. The object I'm trying to deserialize contains a readObject() in one of it's parent classes... XStream will deserialize my object successfully if I don't subclass the object that's serializable. On Mon, Dec 1, 2008 at 12:02 PM, Mark Waschkowski public.gmane.org>wrote:

Re: Conversion Exception

Mark Waschkowski — 2008-12-01T17:02:04

Hi, You would need to provide the xml being unmarshelled. Almost certainly this relates to: http://xstream.codehaus.org/faq.html#XML_unmarshalling_fails I believe if you compare XML created by XStream to the XML you are using you will notice some differences that are causing the problem you encountered. Regards, Mark On Mon, Dec 1, 2008 at 11:54 AM, Lucas Eskopinski public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Conversion Exception

Lucas Eskopinski — 2008-12-01T16:54:27

--------------------------------------------

Issue implementing Serializable interface

Mark Codere — 2008-12-01T16:15:39

Hi Joerg, I am using XStream to deserialize an object from XML and I keep getting the following fail message: com.thoughtworks.xstream.converters.ConversionException: Cannot deserialize object with new readObject()/writeObject() methods ---- Debugging information ---- class : com.Request required-type : com.Request path : /work_request line number : 1 ------------------------------- at com.thoughtworks.xstream.converters.reflection.SerializableConverter.doUnmarshal(SerializableConverter.java:270) at com.thoughtworks.xstream.converters.reflection.AbstractReflectionConverter.unmarshal(AbstractReflectionConverter.java:150) at com.thoughtworks.xstream.core.TreeUnmarshaller.convert(TreeUnmarshaller.java:81) at com.thoughtworks.xstream.core.AbstractReferenceUnmarshaller.convert(AbstractReferenceUnmarshaller.java:55) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:75) at com.thoughtworks.xstream.core.TreeUnmarshaller.convertAnother(TreeUnmarshaller.java:59) at com.thoughtworks.xstream.core.TreeUnmarshaller.start(TreeUnmarshaller.java:142) at com.thoughtworks.xstream.core.AbstractTreeMarshallingStrategy.unmarshal(AbstractTreeMarshallingStrategy.java:33) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:931) at com.thoughtworks.xstream.XStream.unmarshal(XStream.java:917) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:861) at com.thoughtworks.xstream.XStream.fromXML(XStream.java:853) After much digging through XStream source code, it appears that the java object I'm trying to deserialize from the XML is not being created because it's an instance of a class that implements the Serializable interface. It seems as though, a SerializableConverter is being used as opposed to the AbstractReflectionConverter. In the DefaultConverterLookup.lookupConverterForType(), the SerializableConverter is found since it's isSerializable() returns true after passing the serializationMethodInvoker.supportsReadObject() test. The object I'm trying to deserialize contains a readObject() in one of it's parent classes... Thanks, Mark

Re: How to use XSTream to persist a Graph Object??

Mark Waschkowski — 2008-12-01T12:36:15

As I said in my previous email (which you never responded to): -----snip Hi, The simple answer is you can serialize any java object you want. Given your context, you should only persist the data you wish to store. You should create classes that will render the stored data, and you should do it all through an object model. So, change the names as desired, but do something similar to the following: 1) Create a Position class (this stores rotation and distance) 2) Create renderers (or Views) that work with Position objects 3) Persist the Position classes via xstream - your serialized xml will be very simple now Once you apply the concept of a Model (Position) and a View (the renderers), you will notice that its far easier to evolve, maintain and debug your system moving forward. It will take a bit of work to refactor your code, but trust me that it will be worth it, and the next time you do something similar you will be further ahead knowing the proper concepts to apply. Search for Model-View-Controller to find out more. Regards, Mark On Sun, Nov 30, 2008 at 10:38 PM, sunnymanman public.gmane.org> wrote: --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

RE: ClassNotFoundException thrown while deserializing?

Jörg Schaible — 2008-12-01T10:52:16

Hi, rmahmood wrote: OK, then let's rephrase it a bit and provide some pseudo code. Fact is that your current apoproach relies on the client side implementation of the app server's stubs. But I think this detail is not realy of interest! Does it make a difference four your use case whether the EJB call was made against JBoss or WebLogic? AFAICS you should only be interested in the called method of that EJB (stub). Currently you must have implemented something like this (pseudo code): ========= %< =========== class Call { Method method; Object target; Object[] arguments; Object result; public Call(Method method, Object target, Object[] arguments, Object result) { this.method = method; this.target = target; this.arguments = arguments; this.object = object; } } ... result = method.invoke(target, arguments); recoder.add(new Call(method, target, arguments, result)); ... ========= %< =========== but you have to do handle all stubs specially and replace it with an equivalent object (equivalent for the replay of course): ========= %< =========== class Call { ... public Call(Method method, Object target, Object[] arguments, Object result) { this.method = method; this.target = normalize(target); if (arguments == null) this.arguments = null; else { this.arguments = new Object[arguments.length]; for (int i = 0; i < arguments.length; ++i) this.arguments[i] = normalize(arguments[i]); } this.object = normalize(object); } private Object normalize(Object object) { if (!(object instanceof EJBObject)) { return object; } Class[] ifaces = object.getClass().getInterfaces(); return Proxy.newProxyInstance(Thread.currentThread().getContextClassloader(), ifaces, new InvocationHandler() { Object invoke(Objetc proxy, Method method, Object[] args) { throw IllegalStateException("Should not have been called in replay"); } }) } ... } ========= %< =========== That way, you create an own replacement object for the stubs that does not contain app server specific stuff and that can be serialized quite easily. - Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

How to use XSTream to persist a Graph Object??

sunnymanman — 2008-12-01T03:38:10

Hello sir: I hope to use XStream to persist a Graph object as following example I googled in website: 1. main program: import java.awt.*; import java.awt.event.*; import java.awt.geom.*; import javax.swing.*; import javax.swing.event.*; public class Location extends JPanel implements ChangeListener { Ellipse2D.Double ball; Line2D.Double line; JSlider translate; double lastTheta = 0; public void stateChanged(ChangeEvent e) { JSlider slider = (JSlider)e.getSource(); String name = slider.getName(); int value = slider.getValue(); if(name.equals("rotation")) tilt(Math.toRadians(value)); else if(name.equals("translate")) moveBall(value); repaint(); } protected void paintComponent(Graphics g) { super.paintComponent(g); Graphics2D g2 = (Graphics2D)g; g2.setRenderingHint(RenderingHints.KEY_ANTIALIASING, RenderingHints.VALUE_ANTIALIAS_ON); if(ball == null) initGeom(); g2.setPaint(Color.green.darker()); g2.draw(line); g2.setPaint(Color.red); g2.fill(ball); } private void initGeom() { int w = getWidth(); int h = getHeight(); int DIA = 30; int padFromEnd = 5; line = new Line2D.Double(w/4, h*15/16, w*3/4, h*15/16); double x = line.x2 - padFromEnd - DIA; double y = line.y2 - DIA; ball = new Ellipse2D.Double(x, y, DIA, DIA); // update translate slider values int max = (int)line.getP1().distance(line.getP2()); translate.setMaximum(max); translate.setValue(max-padFromEnd); } private void tilt(double theta) { // rotate line from left end Point2D pivot = line.getP1(); double lineLength = pivot.distance(line.getP2()); Point2D.Double p2 = new Point2D.Double(); p2.x = pivot.getX() + lineLength*Math.cos(theta); p2.y = pivot.getY() + lineLength*Math.sin(theta); line.setLine(pivot, p2); // find angle from pivot to ball center relative to line // ie, ball center -> pivot -> line end double cx = ball.getCenterX(); double cy = ball.getCenterY(); double pivotToCenter = pivot.distance(cx, cy); // angle of ball to horizon double dy = cy - pivot.getY(); double dx = cx - pivot.getX(); // relative angle phi = ball_to_horizon - last line_to_horizon double phi = Math.atan2(dy, dx) - lastTheta; // rotate ball from pivot double x = pivot.getX() + pivotToCenter*Math.cos(theta+phi); double y = pivot.getY() + pivotToCenter*Math.sin(theta+phi); ball.setFrameFromCenter(x, y, x+ball.width/2, y+ball.height/2); lastTheta = theta; // save theta for next time } private void moveBall(int distance) { Point2D pivot = line.getP1(); // ball touches line at distance from pivot double contactX = pivot.getX() + distance*Math.cos(lastTheta); double contactY = pivot.getY() + distance*Math.sin(lastTheta); // find new center location of ball // angle lambda = lastTheta - 90 degrees (anti-clockwise) double lambda = lastTheta - Math.PI/2; double x = contactX + (ball.width/2)*Math.cos(lambda); double y = contactY + (ball.height/2)*Math.sin(lambda); ball.setFrameFromCenter(x, y, x+ball.width/2, y+ball.height/2); } JPanel getControls() { JSlider rotate = getSlider("rotation angle", "rotation", -90, 0, 0, 5, 15); translate = getSlider("distance from end", "translate", 0, 100, 100,25, 50); JPanel panel = new JPanel(new GridLayout(0,1)); panel.add(rotate); panel.add(translate); return panel; } private JSlider getSlider(String title, String name, int min, int max, int value, int minorSpace, int majorSpace) { JSlider slider = new JSlider(JSlider.HORIZONTAL, min, max, value); slider.setBorder(BorderFactory.createTitledBorder(title)); slider.setName(name); slider.setPaintTicks(true); slider.setMinorTickSpacing(minorSpace); slider.setMajorTickSpacing(majorSpace); slider.setPaintLabels(true); slider.addChangeListener(this); return slider; } public static void main(String[] args) { Location test = new Location(); JFrame f = new JFrame(); f.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE); f.getContentPane().add(test); f.getContentPane().add(test.getControls(), "Last"); f.setSize(400,400); f.setLocation(200,200); f.setVisible(true); } } OK, 1. I hope After I run it, I made some changes on the picture such as: rotation angle is -45 degree; Distance from the end is 100; I hope to save this CURRENT state into an XML file and save it to disk; 2. then next time I open it, I can read this XML file from disk, and recover whole picture I saved before: rotation angle is -45 degree; Distance from the end is 100; How to use XStream to do this?? Thanks

RE: Custom Mapper

Jörg Schaible — 2008-11-28T12:10:52

Hi Calvin, Wu, Calvin (Technology) wrote on Friday, November 28, 2008 12:51 PM: Mappers and converters are fundamental different things. Since your question imply some lack of understanding (no offence, we do *not* encourage own mappers in first place - it is more like last resort), I'd like to know first, why you think you need a custom mapper? - Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email

Custom Mapper

Wu, Calvin (Technology — 2008-11-28T11:51:21

How do you add a custom mapper to xstream object? Is this only possible via adding a custom converter? Code examples will be much appreciated. Thanks,

RE: CannotResolveClassException in java 1.6

Jörg Schaible — 2008-11-28T07:34:37

Hi Calvin, Calvin Wu wrote: This is a changed behaviour in JDK 6. Yes, http://jira.codehaus.org/browse/XSTR-447 - Jörg --------------------------------------------------------------------- To unsubscribe from this list, please visit: http://xircles.codehaus.org/manage_email