Added error handling

Assignment-2/javaparser-1.0.0/LCA_JP1_0_0.java

@@ -4,33 +4,56 @@ import japa.parser.ast.body.*;
 import japa.parser.ast.visitor.VoidVisitorAdapter;
 
 import java.io.FileInputStream;
+import java.io.IOException;
 import java.io.File;
 
 public class LCA_JP1_0_0 {
 
     public static void main(String[] args) throws Exception {
+        // Checks if file is provided as command line argument
         if (args.length == 0) {
             System.out.println("Usage: java LCA_JP1_0_0 <JavaSourceFile>");
             return;
         }
 
+        // Makes sure file exits and can be read
+        File sourFile = new File(args[0]);
+        if (!sourFile.exists() || !sourFile.isFile() || !sourFile.canRead()) {
+            System.err.println("Error: File can't be read or it doesn't exist: " + args[0]);
+            return;
+        }
+
+        try (FileInputStream in = new FileInputStream(sourFile))
         // Parse the given Java file
-        FileInputStream in = new FileInputStream(new File(args[0]));
+        {
-        CompilationUnit cu = JavaParser.parse(in);
+            CompilationUnit cu;
-
+            try {
-        // Traverse the AST and print local classes
+                cu = JavaParser.parse(in);
-        new VoidVisitorAdapter<Void>() {
+            } catch (Exception e) {
-
+                System.err.println("Error: Failed to parse file");
-            @Override
+                e.printStackTrace();
-            public void visit(MethodDeclaration n, Void arg) {
+                return;
-                super.visit(n, arg);
             }
+            // Traverse the AST and print local classes
+            new VoidVisitorAdapter<Void>() {
 
-            @Override
+                @Override
-            public void visit(ClassOrInterfaceDeclaration n, Void arg) {
+                public void visit(MethodDeclaration n, Void arg) {
-                System.out.println("Found class: " + n.getName());
+                    super.visit(n, arg);
-                super.visit(n, arg);
+                }
-            }
+
-        }.visit(cu, null);
+                @Override
+                public void visit(ClassOrInterfaceDeclaration n, Void arg) {
+                    System.out.println("Found class: " + n.getName());
+                    super.visit(n, arg);
+                }
+            }.visit(cu, null);
+        } catch (IOException e) {
+            System.err.println("Error: Unable to read the file.");
+            e.printStackTrace();
+        } catch (Exception e) {
+            System.err.println("Uneaxpected error occured.");
+            e.printStackTrace();
+        }
     }
 }

Assignment-2/javaparser-1.0.0/test.java

@@ -1,14 +1,17 @@
 public class test {
     void methodOne() {
-        class Helper234 {
+        public class Helper234 {
-            void doStuff() {}
+            void doStuff() {
+            }
         }
-        class Helper2 {
+        private class Helper2 {
-            void doStuff() {}
+            void doStuff() {
+            }
         }
     }
 
     void methodTwo() {
         System.out.println("Hello");
     }
+
 }