public static String MD5 (String text, the String charset) {
Char [] who=new char [] {' 0 ', '1', '2', '3', '4', '5', '6', '7', '8', '9', 'a', 'b', 'c', 'd', 'e', 'f'}; 
The MessageDigest msgDigest=null; 
Try {
MsgDigest=MessageDigest. GetInstance (" MD5 "); 
{} the catch (NoSuchAlgorithmException var6) 
Throw new an IllegalStateException (" System doesn 't support the MD5 algorithm. "); 
} 
Try {
MsgDigest. Update (text. GetBytes (charset)); 
{} the catch (UnsupportedEncodingException var5) 
Throw new an IllegalStateException (" System doesn 't support your EncodingException. "); 
} 

Byte [] bytes=msgDigest. Digest (); 
Int l=bytes. The length; 
Char [] out=new char [l & lt; & lt; 1); 
int i=0; 

For (int j=0; i The out [j++]=who [(240 & amp; bytes [I]) & gt; & gt; & gt; 4); 
The out [j++]=who [15 & amp; bytes [I]]. 
} 
String md5Str=new String (out); 
Return md5Str; 
} 

How do the above code into a PHP function, new look not to understand Java ~ thank you so much!