fix string concatenates performance

src/main/java/fr/xephi/authme/security/crypts/PHPBB.java

@@ -10,7 +10,6 @@ import java.security.MessageDigest;
 import java.security.NoSuchAlgorithmException;
 
 /**
- *
  * @author stefano
  */
 public class PHPBB implements EncryptionMethod {
@@ -20,19 +19,16 @@ public class PHPBB implements EncryptionMethod {
 
     public String phpbb_hash(String password, String salt) {
         String random_state = salt;
-        String random = "";
+        StringBuilder random = new StringBuilder();
         int count = 6;
-        if (random.length() < count) {
-            random = "";
-            for (int i = 0; i < count; i += 16) {
-                random_state = md5(salt + random_state);
-                random += pack(md5(random_state));
-            }
-            random = random.substring(0, count);
+        for (int i = 0; i < count; i += 16) {
+            random_state = md5(salt + random_state);
+            random.append(pack(md5(random_state)));
         }
-        String hash = _hash_crypt_private(password, _hash_gensalt_private(random, itoa64));
-        if (hash.length() == 34)
+        String hash = _hash_crypt_private(password, _hash_gensalt_private(random.substring(0, count), itoa64));
+        if (hash.length() == 34) {
             return hash;
+        }
         return md5(password);
     }
 
@@ -40,9 +36,8 @@ public class PHPBB implements EncryptionMethod {
         return _hash_gensalt_private(input, itoa64, 6);
     }
 
-    @SuppressWarnings("unused")
     private String _hash_gensalt_private(String input, String itoa64,
-            int iteration_count_log2) {
+                                         int iteration_count_log2) {
         if (iteration_count_log2 < 4 || iteration_count_log2 > 31) {
             iteration_count_log2 = 8;
         }
@@ -109,9 +104,7 @@ public class PHPBB implements EncryptionMethod {
             MessageDigest md5er = MessageDigest.getInstance("MD5");
             byte[] hash = md5er.digest(bytes);
             return bytes2hex(hash);
-        } catch (GeneralSecurityException e) {
-            throw new RuntimeException(e);
-        } catch (UnsupportedEncodingException e) {
+        } catch (GeneralSecurityException | UnsupportedEncodingException e) {
             throw new RuntimeException(e);
         }
     }
@@ -126,9 +119,9 @@ public class PHPBB implements EncryptionMethod {
     }
 
     private static String bytes2hex(byte[] bytes) {
-        StringBuffer r = new StringBuffer(32);
-        for (int i = 0; i < bytes.length; i++) {
-            String x = Integer.toHexString(bytes[i] & 0xff);
+        StringBuilder r = new StringBuilder(32);
+        for (byte b : bytes) {
+            String x = Integer.toHexString(b & 0xff);
             if (x.length() < 2)
                 r.append("0");
             r.append(x);
@@ -137,7 +130,7 @@ public class PHPBB implements EncryptionMethod {
     }
 
     static String pack(String hex) {
-        StringBuffer buf = new StringBuffer();
+        StringBuilder buf = new StringBuilder();
         for (int i = 0; i < hex.length(); i += 2) {
             char c1 = hex.charAt(i);
             char c2 = hex.charAt(i + 1);
@@ -155,7 +148,7 @@ public class PHPBB implements EncryptionMethod {
 
     @Override
     public boolean comparePassword(String hash, String password,
-            String playerName) throws NoSuchAlgorithmException {
+                                   String playerName) throws NoSuchAlgorithmException {
         return phpbb_check_hash(password, hash);
     }
 }

src/main/java/fr/xephi/authme/security/crypts/WORDPRESS.java

@@ -8,13 +8,12 @@ import java.util.Arrays;
 
 public class WORDPRESS implements EncryptionMethod {
 
-    private static String itoa64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
-    private int iterationCountLog2 = 8;
+    private static final String itoa64 = "./0123456789ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz";
     private SecureRandom randomGen = new SecureRandom();
 
     private String encode64(byte[] src, int count) {
         int i, value;
-        String output = "";
+        StringBuilder output = new StringBuilder();
         i = 0;
 
         if (src.length < count) {
@@ -26,24 +25,24 @@ public class WORDPRESS implements EncryptionMethod {
         do {
             value = src[i] + (src[i] < 0 ? 256 : 0);
             ++i;
-            output += itoa64.charAt(value & 63);
+            output.append(itoa64.charAt(value & 63));
             if (i < count) {
                 value |= (src[i] + (src[i] < 0 ? 256 : 0)) << 8;
             }
-            output += itoa64.charAt((value >> 6) & 63);
+            output.append(itoa64.charAt((value >> 6) & 63));
             if (i++ >= count) {
                 break;
             }
             if (i < count) {
                 value |= (src[i] + (src[i] < 0 ? 256 : 0)) << 16;
             }
-            output += itoa64.charAt((value >> 12) & 63);
+            output.append(itoa64.charAt((value >> 12) & 63));
             if (i++ >= count) {
                 break;
             }
-            output += itoa64.charAt((value >> 18) & 63);
+            output.append(itoa64.charAt((value >> 18) & 63));
         } while (i < count);
-        return output;
+        return output.toString();
     }
 
     private String crypt(String password, String setting) {
@@ -86,7 +85,8 @@ public class WORDPRESS implements EncryptionMethod {
 
     private String gensaltPrivate(byte[] input) {
         String output = "$P$";
-        output += itoa64.charAt(Math.min(this.iterationCountLog2 + 5, 30));
+        int iterationCountLog2 = 8;
+        output += itoa64.charAt(Math.min(iterationCountLog2 + 5, 30));
         output += encode64(input, 6);
         return output;
     }