fixing warnings errors

Author: nickinhinguyen

src/main/java/command_decorators/CommandDecorator.java

@@ -7,7 +7,7 @@
  */
 public abstract class CommandDecorator extends Command {
     // this is the command we want to decorate
-    Command command;
+    final Command command;
 
     public CommandDecorator(Command command) {
         // create a command decorator with provided command

src/main/java/commands/Cat.java

@@ -28,7 +28,7 @@ public String executeCommand(IShellState shellState, List<String> arguments)
          * and get the directory of the requirement file and its name
          */
         checkArgumentsNum(arguments);
-        String output = "";
+        StringBuilder output = new StringBuilder();
         for (String path: arguments) {
             try {
                 // retrieve the file object at given path
@@ -38,21 +38,21 @@ public String executeCommand(IShellState shellState, List<String> arguments)
                  * else concatenate the current file after the previous
                  * file with 3 lines break
                  */
-                output += (output == "") ?
-                        filetoCat.getContent() : ("\n\n" + filetoCat.getContent());
+                output.append((output.toString().equals("")) ?
+                        filetoCat.getContent() : ("\n\n" + filetoCat.getContent()));
             }
             /*
              * if a file given is invalid, concatenate previous input(if any)
              * with an error string
              */
             catch (Exception e) {
                 String errorString = "cannot view file " + path + ": " + e.getMessage();
-                output += (output == "") ?
-                        errorString:  "\n\n" + errorString;
+                output.append((output.toString().equals("")) ?
+                        errorString : "\n\n" + errorString);
             }
         }
         // return the contents of all files
-        return output;
+        return output.toString();
     }
 
 

src/main/java/commands/Command.java

@@ -9,9 +9,9 @@
  */
 public abstract class Command {
     // this is maximum number of arguments that command takes
-    protected int maxArguments;
+    protected final int maxArguments;
     //this is minimum number of arguments that command takes
-    protected int minArguments;
+    protected final int minArguments;
 
     public Command(int maxArguments, int minArguments) {
         this.maxArguments = maxArguments;

src/main/java/commands/Find.java

@@ -64,8 +64,6 @@ public String executeCommand(IShellState shellState,
                     // if it has a child that is of type directory
                     if (((Directory) fsObject).
                             hasChildWithTypeAndName(Directory.class,name)){
-                        //FileSystemObject child = Directory.
-                        //findChild((Directory)fsObject,name);
                         output = "directory found in " + paths;}
                     // if it has a child that is of type file
                     else if (((Directory) fsObject).

src/main/java/commands/Get.java

@@ -29,13 +29,13 @@ public String executeCommand(IShellState shellState, List<String> arguments)
         Directory currentDir = shellState.getCurrentDir();
 
         //read through each line of the file and append to content
-        String content = "";
+        StringBuilder content = new StringBuilder();
         URL url = new URL(arguments.get(0));
         BufferedReader in = new BufferedReader(
                 new InputStreamReader(url.openStream()));
         String inputLine;
         while ((inputLine = in.readLine()) != null)
-            content += inputLine + "\n";
+            content.append(inputLine).append("\n");
         in.close();
 
         //get the url to find the file name
@@ -46,7 +46,7 @@ public String executeCommand(IShellState shellState, List<String> arguments)
          * create a file in current directory with founded file name
          * and content
          */
-        new file_system.File(fileName, currentDir, content);
+        new file_system.File(fileName, currentDir, content.toString());
 
         return "";
     }

src/main/java/commands/History.java

@@ -45,7 +45,7 @@ private String getHistory(IShellState shellState, int numberOfCommand)
         // get the history list of commands of shellState
         ArrayList<String> history = shellState.getHistory();
         int i = history.size() - 1 ;
-        String output = "";
+        StringBuilder output = new StringBuilder();
         /*
          *  if numberOfCommand exceed the number of history,
          *  set it to print up to all history
@@ -62,10 +62,10 @@ private String getHistory(IShellState shellState, int numberOfCommand)
          * or until all history commands have been printed
          */
         while (numberOfCommand > 0 && i <= history.size()) {
-            output = Integer.toString(i+1) + ". " + history.get(i) + "\n" + output;
+            output.insert(0, i + 1 + ". " + history.get(i) + "\n");
             i--;
             numberOfCommand--;
         }
-        return output;
+        return output.toString();
     }
 }

src/main/java/commands/Load.java

@@ -38,7 +38,7 @@ public String executeCommand(IShellState shellState, List<String> arguments)
             if (path.indexOf("/") == -1) {
                 throw new Exception(Exceptions.WRONG_PATH_INPUT_MSG);
             }
-            String line = null;
+            String line;
 
             FileReader fileReader = new FileReader(path);
             BufferedReader bufferedReader = new BufferedReader(fileReader);
@@ -59,11 +59,11 @@ public String executeCommand(IShellState shellState, List<String> arguments)
                 if (line.equals("*****")) {
                     nextPart = true;
                 }
-                else if (nextPart == false) {
+                else if (!nextPart) {
                     shellState.addHistory(line);
 
                 }
-                else if (nextPart == true) {
+                else{
                     // executeCommand correct command
                     count ++;
                     @SuppressWarnings("unused")

src/main/java/commands/RecursiveInterface.java

@@ -10,6 +10,6 @@
  */
 public interface RecursiveInterface {
     // method for a command to execute recursively
-    public String executeRecursively
-    (IShellState shellState, List<String> arguments) throws Exception ;
+    String executeRecursively
+    (IShellState shellState, List<String> arguments);
 }

src/main/java/driver/IShellState.java

@@ -7,28 +7,28 @@
 import file_system.FileSystem;
 
 public interface IShellState {
-    public boolean isRunning();
+    boolean isRunning();
 
-    public void stopRunning();
+    void stopRunning();
 
-    public FileSystem getFileSystem();
+    FileSystem getFileSystem();
 
-    public Directory getRootDir();
+    Directory getRootDir();
 
-    public Directory getCurrentDir();
+    Directory getCurrentDir();
 
-    public void setCurrentDir(Directory newCurrentDir);
+    void setCurrentDir(Directory newCurrentDir);
 
-    public void addHistory(String inputLine);
+    void addHistory(String inputLine);
 
-    public void removeHistory(int index);
+    void removeHistory(int index);
 
-    public ArrayList<String> getHistory();
+    ArrayList<String> getHistory();
 
-    public void addCorrectHistory(String inputLine);
+    void addCorrectHistory(String inputLine);
 
-    public ArrayList<String> getCorrectHistory();
+    ArrayList<String> getCorrectHistory();
 
-    public Stack<Directory> getDirectoryStack();
+    Stack<Directory> getDirectoryStack();
 
 }