BouncyCastle in Java

Question

I have used the following cod in my program to convert byte to public key

Security.addProvider(new BouncyCastleProvider());
         X509EncodedKeySpec x509keyspec=new X509EncodedKeySpec(b);


         KeyFactory keyfact=KeyFactory.getInstance("RSA","BC");
         Key pubkey=keyfact.generatePublic(x509keyspec); 

I have imported "import org.bouncycastle.jce.provider.BouncyCastleProvider;",.

I have added Bouncycastle.jar file into my jre7/lib/ext folder and made changes in javasecurity file by adding following line security.provider.11=org.bouncycastle.jce.provider.BouncyCastleProvider When i compile code i m getting following error

Reverse.java:14: error: cannot find symbol
import java.security.spec.x509EncodedKeySpecs;
                         ^
symbol:   class x509EncodedKeySpecs
location: package java.security.spec

Reverse.java:16: error: package org.bouncycastle.jce.provider does not exist
import org.bouncycastle.jce.provider.BouncyCastleProvider;

Reverse.java:49: error: cannot find symbol
Security.addProvider(new BouncyCastleProvider());
                                  ^
  symbol:   class BouncyCastleProvider
  location: class Reverse

Solution

Two problems:

• The class is named X509EncodedKeySpec not x509EncodedKeySpecs. Fix your import statement.
• Make sure the BouncyCastle JAR is on the classpath when you compile and run your code.

Comments

[suraj]

BouncyCastle.JAR is in c:program files/jre7/lib/ext folder. Still i am getting errors

[Jesper]

Putting it in the lib/ext folder of the JRE doesn't mean that the Java compiler will automatically pick it up when compiling your program. Make sure it is in the classpath when you compile your program.

[suraj]

Reverse.java:49: error: cannot find symbol Security.addProvider(new BouncyCastleProvider());

[suraj]

In Environment Variable i put a variable called classpath and assigned it path c:program files/jre7/lib/ext/bouncycastle. Still the error is not rectified

[Jesper]

If you literally put c:program files/jre7/lib/ext/bouncycastle in the CLASSPATH, then that's wrong. Add the JAR file to the CLASSPATH correctly. Use the -cp switch on the command line. For example: javac -cp "C:\Program Files\jre7\lib\ext\bouncycastle.jar" Reverse.java

[suraj]

C:\Program Files\Java\jdk1.7.0_02\bin>java -cp . Reverse Exception in thread "main" java.lang.NoClassDefFoundError: org/bouncycastle/jce/ provider/BouncyCastleProvider at java.lang.Class.getDeclaredMethods0(Native Method) at java.lang.Class.privateGetDeclaredMethods(Class.java:2442) at java.lang.Class.getMethod0(Class.java:2685) at java.lang.Class.getMethod(Class.java:1620) at sun.launcher.LauncherHelper.getMainMethod(LauncherHelper.jav‌​a:488) at sun.launcher.LauncherHelper.checkAndLoadMain(LauncherHelper.‌​java:480)

[suraj]

I m using jdk 1.7 and i checked out and found out der is no bouncycastle for jdk1.7. Is dat a issue?

[Jesper]

Also put the JAR in the classpath when running the application: java -cp "C:\Program Files\jre7\lib\ext\bouncycastle.jar;." Reverse