Build the first stage of the Hack Assembler which only assembles the …

…C-Instruction.

assembler/src/java/Assembler.java

@@ -0,0 +1,50 @@
+import java.io.BufferedWriter;
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+import java.io.PrintWriter;
+import java.nio.file.Path;
+import java.nio.file.Paths;
+
+public class Assembler{
+    private static final String OUTPUT_EXTENSION = ".hack";
+
+    public static void main(String[] args) throws IOException{
+        Parser parser;
+        for(String arg: args){
+            File currentFile = new File(arg);
+            String fileName = currentFile.getName();
+            int index = fileName.indexOf(".");
+            if(index > 0)
+                fileName = fileName.substring(0, index);
+            fileName += OUTPUT_EXTENSION;
+            String filePath = Paths.get(currentFile.getParent()).resolve(fileName).toString();
+            File outFile = new File(filePath);
+
+            PrintWriter printW
+                = new PrintWriter(new BufferedWriter(new FileWriter(outFile)));
+
+            parser = new Parser(arg);
+            while(parser.hasMoreCommands()){
+                String line = "";
+                parser.advance();
+                if(parser.commandType() == Parser.CommandType.A_COMMAND
+                    || parser.commandType() == Parser.CommandType.L_COMMAND)
+                    line = parser.symbol();
+                else if(parser.commandType() == Parser.CommandType.C_COMMAND){
+                    String c = parser.comp();
+                    String d = parser.dest();
+                    String j = parser.jump();
+                    String cc = Code.comp(c);
+                    String dd = Code.dest(d);
+                    String jj = Code.jump(j);
+
+                    line = "111" + cc + dd + jj;
+                }
+                printW.println(line);
+            }
+            printW.flush();
+            printW.close();
+        }
+    }
+}