fixes a bug in SignatureAttribute.renameClass().

src/main/javassist/bytecode/SignatureAttribute.java

@@ -131,64 +131,96 @@ public class SignatureAttribute extends AttributeInfo {
             try {
                 while ((c = desc.charAt(++k)) != ';') {
                     if (c == '<') {
-                    	genericParamBuf.append(c);
-                    	int level = 1;
+                        genericParamBuf.append(c);
+                        int level = 1;
                         while (level > 0) {
-                        	c = desc.charAt(++k);
-                        	genericParamBuf.append(c);
-                        	if (c == '<') ++level;
-                        	else if (c == '>') --level;
+                            c = desc.charAt(++k);
+                            genericParamBuf.append(c);
+                            if (c == '<')
+                                ++level;
+                            else if (c == '>')
+                                --level;
                         }
-                    } else if (c == '.') {
-                    	nameBufs.add(nameBuf);
-                    	genericParamBufs.add(genericParamBuf);
-                    	nameBuf = new StringBuilder();
-                    	genericParamBuf = new StringBuilder();
-                    } else {
-                    	nameBuf.append(c);
                     }
+                    else if (c == '.') {
+                        nameBufs.add(nameBuf);
+                        genericParamBufs.add(genericParamBuf);
+                        nameBuf = new StringBuilder();
+                        genericParamBuf = new StringBuilder();
+                    }
+                    else
+                        nameBuf.append(c);
                 }
             }
             catch (IndexOutOfBoundsException e) { break; }
 
             nameBufs.add(nameBuf);
-        	  genericParamBufs.add(genericParamBuf);
+            genericParamBufs.add(genericParamBuf);
             i = k + 1;
-            
+
             String name = String.join("$", nameBufs.toArray(new StringBuilder[0]));
             String newname = map.get(name);
             if (newname != null) {
                 final String[] nameSplit = name.split("\\$");
                 final String[] newnameSplit = newname.split("\\$");
-            	if (nameSplit.length == newnameSplit.length) {
-            		final String[] newnames = new String[nameBufs.size()];
-            		for (int start = 0, z = 0; z < nameBufs.size(); ++z) {
-            			final int toAggregate = (int) nameBufs.get(z).chars().filter(ch -> ch == '$').count() + 1;
-            			String s = String.join("$", Arrays.copyOfRange(newnameSplit, start, start + toAggregate));
-            			start += toAggregate;
-            			newnames[z] = s;
-            		}
-            		
-            		
-            		newdesc.append(desc.substring(head, j));
-            		newdesc.append('L');
-            		for (int z = 0; z < newnames.length; ++z) {
-            			if (z > 0) {
-            				newdesc.append('.');
-            			}
-            			newdesc.append(newnames[z]);
-            			final String newgenericParam;
-            			final StringBuilder genericParamBufCurrent = genericParamBufs.get(z);
-            			if (genericParamBufCurrent.length() > 0) {
-            				newgenericParam = "<" + renameClass(genericParamBufCurrent.substring(1, genericParamBufCurrent.length() - 1), map) + ">";
-            			} else {
-            				newgenericParam = genericParamBufCurrent.toString(); //empty string
-            			}
-            			newdesc.append(newgenericParam);
-            		}
-            		newdesc.append(c); //the final semicolon
-            		head = i;
-            	}
+                if (nameSplit.length == newnameSplit.length) {
+                    final String[] newnames = new String[nameBufs.size()];
+                    for (int start = 0, z = 0; z < nameBufs.size(); z++) {
+                        final int toAggregate = (int) nameBufs.get(z).chars().filter(ch -> ch == '$').count() + 1;
+                        String s = String.join("$", Arrays.copyOfRange(newnameSplit, start, start + toAggregate));
+                        start += toAggregate;
+                        newnames[z] = s;
+                    }
+
+                    newdesc.append(desc.substring(head, j));
+                    newdesc.append('L');
+                    for (int z = 0; z < newnames.length; z++) {
+                        if (z > 0)
+                            newdesc.append('.');
+
+                        newdesc.append(newnames[z]);
+                        final String newgenericParam;
+                        final StringBuilder genericParamBufCurrent = genericParamBufs.get(z);
+                        if (genericParamBufCurrent.length() > 0)
+                            newgenericParam = "<" + renameClass(genericParamBufCurrent.substring(1, genericParamBufCurrent.length() - 1), map) + ">";
+                        else
+                            newgenericParam = genericParamBufCurrent.toString(); //empty string
+
+                        newdesc.append(newgenericParam);
+                    }
+                    newdesc.append(c); //the final semicolon
+                    head = i;
+                }
+            }
+            else {
+                    final ArrayList<String> newGenericParamBufs = new ArrayList<String>();
+                    boolean changed = false;
+                    for (int z = 0; z < genericParamBufs.size(); z++) {
+                        final String newGenericParam;
+                        final StringBuilder genericParamBufCurrent = genericParamBufs.get(z);
+                        if (genericParamBufCurrent.length() > 0) {
+                            newGenericParam = "<" + renameClass(genericParamBufCurrent.substring(1, genericParamBufCurrent.length() - 1), map) + ">";
+                            changed = changed || !genericParamBufCurrent.toString().equals(newGenericParam);
+                        }
+                        else
+                            newGenericParam = genericParamBufCurrent.toString(); //empty string
+
+                        newGenericParamBufs.add(newGenericParam);
+                    }
+
+                    if (changed) {
+                        newdesc.append(desc.substring(head, j));
+                        newdesc.append('L');
+                        for (int z = 0; z < genericParamBufs.size(); z++) {
+                            if (z > 0)
+                                newdesc.append('.');
+
+                            newdesc.append(nameBufs.get(z));
+                            newdesc.append(newGenericParamBufs.get(z));
+                        }
+                        newdesc.append(';');
+                        head = i;
+                    }
             }
         }