title: java.security AES encryption key length
body: <p>When the key length is 128 bits,everything works. But I got the following exception when I use a key of length 192 or 256 bits.</p>
  
  <pre><code>java.security.InvalidKeyException: Illegal key size or default parameters
  at javax.crypto.Cipher.a(DashoA13*..)
  at javax.crypto.Cipher.a(DashoA13*..)
  at javax.crypto.Cipher.a(DashoA13*..)
  at javax.crypto.Cipher.init(DashoA13*..)
  at javax.crypto.Cipher.init(DashoA13*..)
  </code></pre>
  
  <p>I found this <a href="https://stackoverflow.com/questions/6481627/java-security-illegal-key-size-or-default-parameters">Java Security: Illegal key size or default parameters?</a>. But after I download the jar files and put it in <code>${java.home}/lib/security/</code>, I still got the same exception.</p>