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Java lang securityexception

java.lang.SecurityException – How to solve SecurityException

In this tutorial we will discuss about SecurityException in Java. This exception is thrown by the security manager, in order to indicate a security violation.

The SecurityException class extends the RuntimeException class and thus, belongs to those exceptions that can be thrown during the operation of the Java Virtual Machine (JVM). It is an unchecked exception and thus, it does not need to be declared in a method’s or a constructor’s throws clause.

Finally the SecurityException class exists since the 1.0 version of Java.

The Structure of SecurityException

Constructors

  • SecurityException()

Creates an instance of the SecurityException class, setting null as its message.

SecurityException(String s)

Creates an instance of the SecurityException class, using the specified string as message. The string argument indicates the name of the class that threw the error.

SecurityException(String message, Throwable cause)

Creates an instance of the SecurityException class, using the specified string as message and the specified Throwable as its cause.

SecurityException(Throwable cause)

Creates an instance of the SecurityException class, using the specified Throwable as its cause.

The SecurityException in Java

The SecurityException indicates that a security violation has occurred an thus, the application cannot be executed. A simple example is to use a package name that is already defined in Java.

For example, let’s create a simple hierarchy, where the parent directory is called java and the sub-directory is called util . Then, we create a sample Java class inside the java/util/ directory, which only prints a message:

We compile and execute our sample code by issuing the following commands:

A sample execution is shown below:

When the Java Virtual Machine (JVM) tries to load our class, it recognizes its package name as invalid and thus, a SecurityException is thrown.

How to deal with the SecurityException

  • In the aforementioned case, it is sufficient to change the package name of your application, in order to be executed by the Java Virtual Machine (JVM). In general, you must avoid using package names that are reserved by Java.
  • Sometimes, executing a .jar file can result in a SecurityException be possibly thrown. In such cases, you must verify that the .jar file is properly signed, otherwise you will not be able to execute it. For more information on how to sign a .jar please refer to the instructions here.
  • Finally, running an applet from an external source may also result in a SecurityException be thrown. The most frequent reason is that Java applications are blocked by the underlying security settings. For more information on how to change these settings and how to update your Exception Site list, please refer to the instructions here.

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thanks sir..
security exception is a rare topic i found in internet and the best of them are gets from your site..

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why `java.lang.SecurityException: Prohibited package name: java` is required?

I created a class «String» and placed that in package «java» [ actually i wanted to create java.lang to see which class is loaded by classLoader as

Once a class is loaded into a JVM, the same class (I repeat, the same class) will not be loaded again

quoted from oreilly ] . But that thing later, why on running this class i am getting
java.lang.SecurityException: Prohibited package name: java

For which security reason java is not allowing me to have a class in java package? What one could do if there will not be no such check?

8 Answers 8

User code is never allowed to put classes into one of the standard Java packages. That way, user code cannot access any package-private classes/methods/fields in the Java implementation. Some of those package-private objects allow access to JVM internals. (I’m thinking of SharedSecrets in particular.)

Firstly, these types of restrictions are in place to enforce the Java sandbox. That is, running untrusted code in a trusted environment. Such as running an applet from some site (that you don’t necessarily trust), on your computer (the trusted environment) in your browser. The intent is to disallow untrusted code from gaining access to package-private stuff which could help it escape the sandbox.

Normally these restrictions are enforced by the SecurityManager, so they shouldn’t happen when you run your own application on the command-line (unless you explicitly specify to use a SecurityManager). When you control the environment, you could just go and edit the String.class definition inside the rt.jar of your Java (and you can, technically anyway, not sure what licensing says). As I said the restrictions are normally in the SecurityManager, but this particular rule about java.* packages is in the ClassLoader class.

To answer your question: My guess is that java.* check is there because of a) historic reasons b) somewhere in the Java core there’s a check on the name of the class, something like: All class that start with java.* get special treatment.

However, consider that even if you managed to create a class called java.lang.String, it would not be the same class as the java.lang.String defined by the Java core. It would just be a class with the exact same name. Class identity is more than just the name of the class, even though this can be tricky to perceive unless you really play with ClassLoaders.

So a class loaded by the application classloader in the package java.lang, would not have access to the core java.lang package-private stuff.

To illustrate this, try to create a class called javax.swing.JButton with a main method and execute it. You’ll get a java.lang.NoSuchMethodError: main . That’s because java finds the «real» JButton before your class, and the real JButton doesn’t have a main method.

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In a Java standalone application you might be able to go around this restriction by calling one of the private native defineClassx methods directly via use of reflection and setAccessible.

java.lang.SecurityException: Not allowed to bind to service Intent #31

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pvagner commented Dec 17, 2012

Today morning I have compiled the latest code and espeak is not speaking.
I was testing with the spiel screen reader because I need to use other tts engine as the default in order to be able to do something with my phone.
Here is a logcat excerpt

W/ActivityManager( 2119): Permission denied: checkComponentPermission() owningU > W/ActivityManager( 2119): Permission Denial: Accessing service ComponentInfo from p > I/AudioService( 2119): AudioFocus abandonAudioFocus() from android.media.AudioManager@4191a6e8info.spielproject.spiel.TTS$@41819b28
E/spiel ( 4336): TTS error:
E/spiel ( 4336): java.lang.SecurityException: Not allowed to bind to service Intent

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pvagner commented Dec 17, 2012

One problem in the android manifest is the fact that activities which should be also inwoked from othr apps should not have android:exported property set to false. I have tried to change that but there is more and I am unable to figure it out. Other relevant info is that the app runs fine inside the emulator but gives this error while running on a real device. Common problems of this type include multiple activity definitions with the same name but I think this is not the case here.
I think this is urgent because without this the app is not usable. I will play with this a bit more tonight if there will be no fix.

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rhdunn commented Dec 17, 2012

The security issue could be that the package has not been signed (as it is a development build). Have you enabled the «Unknown sources (Allow install of non-Market applications)» option in the «Settings > Applications» options?

It will work fine under the emulator as the emulator allows unsigned apk files (to support apk development).

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rhdunn commented Dec 17, 2012

With the andro warning. It looks as if I need to address this warning in a different way.

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pvagner commented Dec 17, 2012

I have enabled installation of applications from unknown sources, I am also signing this app with my self-signed certificate. On thursday evening the source code compiled fine.And it was possible to inwoke the service while running on a device.
Perhaps we do need some permission in order to be able to create services or something.

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rhdunn commented Dec 17, 2012

From what I understand, using andro should work — the various services and activities are created through Intents, not explicitly by class name.

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I have found reference to the «java.lang.SecurityException: Not allowed to bind to service Intent» error:

A Google search also yields more results, I am sifting through them now to better understand the problem.

According to the stack overflow page, it is due to another process trying to access the text-to-speech service (in this case, the spiel application). Specifying a remote process should fix the issue.

I have committed the change to add an android:process and tested it on an Android 4.1.2 emulator using the «Listen to an example» which still works. Does this address the issue you are experiencing?

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pvagner commented Dec 17, 2012

well I am just compiling the updated code. However I am afraid you might have missunderstood my report.
This is not failing with spiel but this is failing with any application. I am unable to try whether the sample text will work because as long as I change to espeak in the text to speech settings I am loosing speech output all together and the only way to return the speech back is to use sqlite through adb and change the settings manually in the secure database. This is not because of the technical problems but simply that I need a working speech for manipulating the device since I am blind.

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rhdunn commented Dec 17, 2012

The java.lang.SecurityException should apply to all applications. I mentioned spiel in the commit as you mentioned it in the report.

I know there is an issue where nothing gets played on 2.1 to 3.x devices (issue #27) which happened for me around the time you mention. I am not sure what is causing that appart from getTtsEngine is not being called for some reason. That should not affect Android 4.0 or later, as they use the newer API.

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pvagner commented Dec 17, 2012

unfortunatelly this is not fixed by the commit you are talking about.
I am not sure but what has changed we are now targetting android api 17 before we were targetting android api 14. I am still using the latest platform 17 I am just speculating what has changed since thurstday.

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rhdunn commented Dec 17, 2012

Thank you for testing this.

What manufacturer and Android version is your phone running?

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pvagner commented Dec 17, 2012

Hello,
I do have Samsung Galaxy S II GTI9100 running CM-10 Android 4.1.2.

Now I managed to also capture the log while trying to switch to eSpeak
using text to speech setting.

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