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Java Forum / First Aid / May 2008problem: security using IDE's appletviewer
Hi All, Viewing an image, this applet, which compiles and shows an image in the browser page IE with no error. The image is located >outside< of the program folder. I am having the problem with the IDE's appletviewer that will not allow a image file to be read. The error message on the AppletViewer's message bar at run time is: exception:java.security.AccessControlException:Access denied(java.io.FilePermission \C:\JBsm.jpg read) That said, I have looked at Canadian Mind Products > P words > policy The instructions say to use: grant { permission java.security.AllPermission; }; I have added these lines above but now there is an error at compile time for this applet: <identifier> expected (obviously after the word "grant") Something is missing but I have no idea. I am using jdk1.5.0_12 and jre1.5.0_12 and stored in that same folder is there jre1.6.0_03 and jre1.6.0_05 Thanks in advance for your help. Here is the applet code: import java.awt.*; import java.applet.Applet; import java.awt.Image; public class ImageApplet extends Applet { private Image ioStream; private String errorMessage = null; public void init() { try { //ioStream = getImage(getCodeBase(), // "image/JBsm.JPG" ); //above line works with both the IE browser page // and applet viewer ioStream = getImage(getCodeBase(), "file:/C:/JBsm.JPG" ); //above line works with the Browser page but fails //using the applet viewer //Insure image is downloaded before showing it MediaTracker tracker = new MediaTracker( this ); tracker.addImage( ioStream, 0 ); tracker.waitForID( 0 ); repaint(); } catch (InterruptedException netProblem ) { errorMessage = "Could not reach image"; } } public void paint( Graphics display) { if ( errorMessage == null ) display.drawImage( ioStream, 0, 0, this ); else display.drawString( errorMessage, 10, 10 ); } } bH > That said, I have looked at Canadian Mind Products > > P words > policy [quoted text clipped - 8 lines] > compile time for this applet: > <identifier> expected (obviously after the word "grant") Read the rest of Roedy's page. Especially the part where he tells you that the policy file is outside of your program. <quote> Where are the policy files? Exactly how many policy files you have and where they are is controlled by settings in the C:\Program Files\java\jre1.6.0_06\lib\security\java.security or C:\Program Files\Java Web Start\java.security. The Opera browser has its own policy file at C:\Program Files\Opera\classes\Opera.policy. The default is to have: 1. a single system-wide policy file J:\Program Files\java\jdk1.6.0_06\jre\lib\security\java.policy in the java.home\lib\security directory. 2. a user-specific policy file user.home/.java.policy, e.g. "C:\Documents and Settings\%username%\.java.policy". In Vista, look in "C:\Users\%username%\.java.policy". </quote> > //ioStream = getImage(getCodeBase(), > // "image/JBsm.JPG" ); [quoted text clipped - 4 lines] > //above line works with the Browser page but fails > //using the applet viewer Realistically, this isn't going to work. No one but you is going to edit their own policy files. Make this image into a resource, and use getResourceAsStream(). That's the correct way to package extra files with an applet. > Hi All, > [quoted text clipped - 76 lines] > > bH If you are using the appletviewer or browser to read files from the local disk, they must be in the same directory as the applet class files. When downloading from the net, the files to be read must be served up by the same server that served the applet class files. As for the MediaTracker, it is redundant in your code. If you don't need any information from the Image before displaying it, the ImageObserver (the 'this' in the drawImage() method) will do everything you need to get the image drawn. Also the repaint() call is not required either. As Mark mentioned, you can embed the image file into a jar and serve them up that way. If you jar up your Applet, access the image file with; getImage(getClass().getResource("fname.jpg")); You can specify a directory for the image file but that directory must be stored in your .jar file.  SignatureKnute Johnson email s/nospam/linux/ >That said, I have looked at Canadian Mind Products > > P words > policy [quoted text clipped - 4 lines] >permission java.security.AllPermission; >}; you have to correct the right file. Your IDE may be using a different JVM. Find all the .policy files on your machine and fix them. That's a fairly dangerous thing to do. That turns off all security for all apps anywhere. SignatureRoedy Green Canadian Mind Products The Java Glossary http://mindprod.com On May 6, 1:19 am, Roedy Green <see_webs...@mindprod.com.invalid> wrote: > >That said, I have looked at Canadian Mind Products > > > P words > policy [quoted text clipped - 16 lines] > Roedy Green Canadian Mind Products > The Java Glossaryhttp://mindprod.com Hi Knute, You wrote "If you jar up your Applet, access the image file with; getImage(getClass().getResource ("fname.jpg")); The applet is correctly jar'd along with the image and shows as expected when the jar is opened. I have tested to see that it does work. I do not know what, if anything, goes into the () of getImage(getClass().getResource()) to exctract only the image from the jar by itself, so that the image can go into another program in the same folder. import java.awt.*; import java.applet.Applet; import java.awt.Image; public class ImageAppletBriefX extends Applet { private Image ioStream; private String errorMessage = null; public void init() { try { // the jar containing the image is //"TestLoadImage.jar" // the image file in the jar is "JBsm.JPG" ioStream = getImage(getClass().getResource()); // << the line in question is above repaint(); } catch (Exception netProblem ) { errorMessage = "Could not reach image"; } } public void paint( Graphics display) { if ( errorMessage == null ) display.drawImage( ioStream, 0, 0, this ); else display.drawString( errorMessage, 10, 10 ); } } Thanks for your help up to this point bH Hi Roedy, I no longer desire to change the policy files. your advice "That's a fairly dangerous thing to do. That turns off all security for all apps anywhere" is well taken. bH > Hi Knute, > You wrote "If you jar up your Applet, access the [quoted text clipped - 47 lines] > > bH I'm not exactly clear what your problem is here. But I will give you a complete example. Assume you have an image file named "kittens.jpg" and you want to display it in your Applet. Furthermore you want to deploy your Applet from a .jar file with the code and image store in the .jar. import java.applet.*; import java.awt.*; public class test1 extends Applet { Image image; public void init() { image = getImage(getClass().getResource("kittens.jpg")); } public void paint(Graphics g) { g.setColor(Color.RED); if (!g.drawImage(image,0,0,this)) g.drawString("Loading Image",10,20); } } Compile the code above. Jar up the file with the following command; jar cvfM test1.jar test1*.class kittens.jpg This stores all class files from the test1 class and the image file into the jar. <html> <head> </head> <body> <applet archive="test1.jar" code="test1.class" width="640" height="480"> </applet> </body> </html> Create the html file above, I called mine test1.html. Now run the appletviewer or load the html file with your browser; appletviewer test1.html The appletviewer/browser will load the .jar file and run the test1.class, reading the kittens.jpg image file from the .jar and displaying it. Until the image is completely loaded the message "Loading Image" will be drawn onto the Applet as well. You do not need a repaint() call if you are using the ImageProducer/ImageObserver scheme. If that is not what you needed, then please post again. SignatureKnute Johnson email s/nospam/linux/ On May 7, 1:41 am, Knute Johnson <nos...@rabbitbrush.frazmtn.com> wrote: > > Hi Knute, > > You wrote "If you jar up your Applet, access the [quoted text clipped - 88 lines] > </body> > </html> > Create the html file above, I called mine test1.html. > [quoted text clipped - 23 lines] > > - Show quoted text - Hi Knute, I was able to accomplish your html model above earlier and it did show the image as the original applet did, Thank you for your html gift above. Now for the rest of it. I was hoping that I might extract the image "kittens.jpg" ONLY from the "test1.jar" and use the the image in another applet. All be it by coding differently in a second applet, and make "kittens.jpg" appeared as coming from the jar. I guess that what I was trying to do was make some sense out of what Mark Space was saying above.... "Make this image into a resource, and use getResourceAsStream(). That's the correct way to package extra files with an applet." Can this be changed to reflect getting the image from the jar? image = getImage(getClass().getResource("kittens.jpg")); Any possibility of coding to get just the image ("kittens.jpg") into another applet using that with the idea that Mark Space is saying. If that is not what he was suggesting then there is nothing more. Thanks for your prompt reply. bH > On May 7, 1:41 am, Knute Johnson <nos...@rabbitbrush.frazmtn.com> > wrote: [quoted text clipped - 129 lines] > Can this be changed to reflect getting the image from the jar? > image = getImage(getClass().getResource("kittens.jpg")); getResourceAsStream() just gets you the image data in a stream as opposed to the URL. That won't help you with your question. > Any possibility of coding to get just the image ("kittens.jpg") into > another applet using that with the idea that Mark Space is saying. [quoted text clipped - 3 lines] > > bH Yes. You can specify many .jar files in the ARCHIVE parameter of the APPLET tag. Just separate them with commas. <html> <head> </head> <body> <applet archive="test1.jar,test2.jar" code="test2.class" width="640" height="480"> </applet> </body> </html> The HTML above loads both the test1.jar and test2.jar and runs the class test2. The code for test2.java is almost the same as test1.java. import java.applet.*; import java.awt.*; public class test2 extends Applet { Image image; public void init() { image = getImage(getClass().getResource("kittens.jpg")); } public void paint(Graphics g) { g.setColor(Color.BLUE); if (!g.drawImage(image,0,0,this)) g.drawString("Loading Image",10,20); } } SignatureKnute Johnson email s/nospam/linux/ On May 7, 12:26 pm, Knute Johnson <nos...@rabbitbrush.frazmtn.com> wrote: > > On May 7, 1:41 am, Knute Johnson <nos...@rabbitbrush.frazmtn.com> > > wrote: [quoted text clipped - 187 lines] > > - Show quoted text - Hi Knute, Sorry but I cannot put this away because I cannot understand something. You have the image in a ("kittens.jpg") in a jar that has the name "KnutesTest1.jar" (I made that name up here for the discussion). I am now going to run your "test2" and I use your program above that is supposed to access "KnutesTest1.jar" to grab the image "kittens.jpg". Yet in "test2" there is no clue that I can see where it is find the image you referred in test2: "image = getImage(getClass().getResource("kittens.jpg"));" It can't grab resources that, I don't think, that are not stated. Can you please clarify? TIA, bH >> Yes. You can specify many .jar files in the ARCHIVE parameter of the >> APPLET tag. Just separate them with commas. [quoted text clipped - 68 lines] > > bH The answer is in the HTML file. Note that both test1.jar and test2.jar are listed in the ARCHIVE element of the APPLET tag. The browser or appletviewer will load all .jar files listed there. All classes and files in both .jar files are available to the applet. In the HTML above I tell it to run the test2.class. Does that explain it for you? SignatureKnute Johnson email s/nospam/linux/ ------->>>>>>http://www.NewsDem On May 7, 4:09 pm, Knute Johnson <nos...@rabbitbrush.frazmtn.com> wrote: > >> Yes. You can specify many .jar files in the ARCHIVE parameter of the > >> APPLET tag. Just separate them with commas. [quoted text clipped - 85 lines] > > - Show quoted text - Hi Knute, Sorry to report that your latest gifts do not work: the image will not be pulled out of another jar.... plain and simple, not with the code that you wrote. In summary the (test1.jar and test2.jar) contain identical images and making the test2.class to look into test1.jar for the image, it shows nothing when the html page shows the archive to have both of the jars and even when I remove the second jar and have only the archive showing the first jar, and call for the test2.class to be executed, no image is displayed. Also my research on the net shows nothing but confusion and countless attempts to write something to get images out of the jars. http://java.sun.com/docs/books/tutorial/deployment/jar/unpack.html (comment: shows how to do it with the cmd.exe) my reaction "ugh" http://forum.java.sun.com/thread.jspa?threadID=748643&messageID=4290284#4290284 (comment: Java Archive (JAR) Files - extracting to a certain directory) instructions http://forum.java.sun.com/thread.jspa?threadID=330269&messageID=1792680#1792680 (comment : topic here is: I can't get some Images to load when they are in jar files) Knute, Thanks again for your efforts. I have used up my patience and possibly yours too. bH > On May 7, 4:09 pm, Knute Johnson <nos...@rabbitbrush.frazmtn.com> > wrote: [quoted text clipped - 101 lines] > > bH This does work. Go to http://rabbitbrush.frazmtn.com/test/ and click on the test1.html file. It will load two applets that both access the images.jar file that contains my kittens.jpg image. Look at the source code for the HTML page and the two Java Applets, test1 and test2. I put these in a package but that is not required. This is done every day even though you've found a lot of people that are having problems, it does work. SignatureKnute Johnson email s/nospam/linux/ On May 8, 1:16 am, Knute Johnson <nos...@rabbitbrush.frazmtn.com> wrote: > > On May 7, 4:09 pm, Knute Johnson <nos...@rabbitbrush.frazmtn.com> > > wrote: [quoted text clipped - 121 lines] > > - Show quoted text - Hi Knute, Thanks for the demo. I didn't know that one could jar the image, never did that before. I didn't see a manifest in your testX.jars, but who needs them when it works like this. I didn't see that way of writing the html page either. As a mathematician who ordered a new suit from a tailor and at try on time, said to his tailor "This suit doesn't fit. Look the right sleeve of the jacket is too short. And the jacket is too tight. Look at the pants, the left pants leg needs to be shorter”. To which the tailor replied "When you walk suck in your bay window, hike up your right shoulder so that the right sleeve is at the same length as the left, and take a longer step with your left leg. The mathematician looked bewildered at the tailor's directions. The tailor replied "You'll get used to walking that way, the way I had to get used to figuring out math problems when I took the course you taught". bH > As a mathematician who ordered a new suit from a tailor and at try on > time, said to his tailor "This suit doesn't fit. Look the right sleeve [quoted text clipped - 10 lines] > to get used to figuring out math problems when I took the course you > taught". Having bought the suit, with his belly sucked in, one shoulder hiked, the hips cocked so the pants legs would look the same length, torso twisted so the jacket would drape, the mathematician left the tailor's shop, rather disgruntled. As he walked, hobbled, really, to keep the pants balanced, a man walked up to him. "Is that a new suit? It looks nice!" the man said. "Why, yes," the mathematician replied, thinking, maybe this tailor wasn't so bad after all. "Where'd you get it done?" the man inquired. "At the tailor's on the corner back there," the mathematician responded. "I've got to see him!" the man enthused. "Anyone who can fit someone as misshapen as you must be a genius!" SignatureLew > > As a mathematician who ordered a new suit from a tailor and at try on > > time, said to his tailor "This suit doesn't fit. Look the right sleeve [quoted text clipped - 31 lines] > -- > Lew Hi Lew, Beautiful ending, I could not recall the "rest of the story", as it was nearly 1 A.M. in my part of the world when I wrote it, and especially after frustrating days of digging the mines of Sun and Google, looking for this diamond for the world to see. bH Free MagazinesGet these publications absolutely FREE for up to 12 months. There are no hidden fees and no obligation. 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