Refactored the lisp interpreter builder and some error handling

src/environment/RuntimeEnvironment.java

@@ -2,6 +2,8 @@ package environment;
 
 import java.io.*;
 
+import error.ErrorManager;
+
 public class RuntimeEnvironment {
 
     private static RuntimeEnvironment uniqueInstance = new RuntimeEnvironment();
@@ -10,14 +12,20 @@ public class RuntimeEnvironment {
         return uniqueInstance;
     }
 
+    private String inputName;
     private InputStream input;
     private PrintStream output;
     private PrintStream errorOutput;
     private Runnable terminationFunction;
     private Runnable errorTerminationFunction;
+    private ErrorManager errorManager;
 
     private RuntimeEnvironment() {}
     
+    public void setInputName(String inputName) {
+        this.inputName = inputName;
+    }
+
     public void setInput(InputStream input) {
         this.input = input;
     }
@@ -38,12 +46,16 @@ public class RuntimeEnvironment {
         this.errorTerminationFunction = errorTerminationFunction;
     }
     
-    public InputStream getInput() {
-        return input;
+    public void setErrorManager(ErrorManager errorManager) {
+        this.errorManager = errorManager;
     }
     
     public String getInputName() {
-        return input.toString();
+        return inputName;
+    }
+
+    public InputStream getInput() {
+        return input;
     }
 
     public PrintStream getOutput() {
@@ -62,4 +74,8 @@ public class RuntimeEnvironment {
         errorTerminationFunction.run();
     }
     
+    public ErrorManager getErrorManager() {
+        return errorManager;
+    }
+
 }

src/error/LispException.java

@@ -4,6 +4,18 @@ public abstract class LispException extends RuntimeException {
 
     private static final long serialVersionUID = 1L;
 
+    public static final LispException convertToLispException(RuntimeException e) {
+        return new LispException() {
+
+            private static final long serialVersionUID = 1L;
+
+            @Override
+            public String getMessage() {
+                return e.getMessage();
+            }
+        };
+    }
+
     public int getSeverity() {
         return 0;
     }

src/function/builtin/LOAD.java

@@ -1,9 +1,12 @@
 package function.builtin;
 
+import static error.LispException.convertToLispException;
+
 import java.io.*;
 import java.text.MessageFormat;
 
 import environment.RuntimeEnvironment;
+import error.*;
 import function.*;
 import parser.LispParser;
 import sexpression.*;
@@ -12,12 +15,14 @@ public class LOAD extends LispFunction {
 
     private ArgumentValidator argumentValidator;
     private RuntimeEnvironment environment;
+    private ErrorManager errorManager;
 
     public LOAD() {
         this.argumentValidator = new ArgumentValidator("LOAD");
         this.argumentValidator.setExactNumberOfArguments(1);
         this.argumentValidator.setEveryArgumentExpectedType(LispString.class);
         this.environment = RuntimeEnvironment.getInstance();
+        this.errorManager = this.environment.getErrorManager();
     }
 
     public SExpression call(Cons argumentList) {
@@ -49,7 +54,7 @@ public class LOAD extends LispFunction {
         try {
             parser = new LispParser(new FileInputStream(fileName), fileName);
         } catch (FileNotFoundException e) {
-            printCouldNotOpenFileMessage(fileName);
+            errorManager.generateError(new CouldNotLoadFileException(fileName));
         }
 
         return parser;
@@ -58,12 +63,12 @@ public class LOAD extends LispFunction {
     private boolean isSuccessfulEvaluation(LispParser parser) {
         while (!parser.isEof()) {
             try {
-                SExpression sexpr = parser.getNextSExpression();
-
-                EVAL.eval(sexpr);
+                EVAL.eval(parser.getNextSExpression());
+            } catch (LispException e) {
+                errorManager.generateError(e);
+                return false;
             } catch (RuntimeException e) {
-                printErrorMessage(e.getMessage());
-
+                errorManager.generateError(convertToLispException(e));
                 return false;
             }
         }
@@ -71,14 +76,19 @@ public class LOAD extends LispFunction {
         return true;
     }
 
-    private void printCouldNotOpenFileMessage(String fileName) {
-        String message = MessageFormat.format("could not open ''{0}''", fileName);
-        printErrorMessage(message);
-    }
+    public static class CouldNotLoadFileException extends LispException {
 
-    private void printErrorMessage(String errorMessage) {
-        String message = MessageFormat.format("LOAD: {0}", errorMessage);
-        environment.getErrorOutput().println(message);
+        private static final long serialVersionUID = 1L;
+        private String fileName;
+
+        public CouldNotLoadFileException(String fileName) {
+            this.fileName = fileName;
+        }
+
+        @Override
+        public String getMessage() {
+            return MessageFormat.format("could not load ''{0}''", fileName);
+        }
     }
 
 }

src/interpreter/InteractiveLispInterpreter.java

@@ -2,7 +2,7 @@ package interpreter;
 
 public class InteractiveLispInterpreter extends LispInterpreter {
 
-    private static final String GREETING = "SUNY Potsdam Lisp Interpreter - Version 4.4.3";
+    private static final String GREETING = "SUNY Potsdam Lisp Interpreter - Version 1.0.0";
     private static final String PROMPT = "~ ";
 
     @Override

src/interpreter/LispInterpreter.java

@@ -1,6 +1,7 @@
 package interpreter;
 
-import java.io.*;
+import static error.LispException.convertToLispException;
+
 import java.text.MessageFormat;
 
 import environment.RuntimeEnvironment;
@@ -14,26 +15,13 @@ public class LispInterpreter {
     public static final String ANSI_RESET = "\u001B[0m";
     public static final String ANSI_GREEN = "\u001B[32m";
 
-    private LispParser parser;
-    private ErrorManager errorManager;
     protected RuntimeEnvironment environment;
+    protected ErrorManager errorManager;
+    private LispParser parser;
 
     public LispInterpreter() {
         this.environment = RuntimeEnvironment.getInstance();
-        this.errorManager = new ErrorManager();
-        this.parser = new LispParser(this.environment.getInput(), this.environment.getInputName());
-    }
-
-    public LispInterpreter(String fileName) {
-        this.environment = RuntimeEnvironment.getInstance();
-        this.errorManager = new ErrorManager();
-
-        try {
-            this.environment.setInput(new FileInputStream(fileName));
-        } catch (FileNotFoundException e) {
-            this.errorManager.generateError(new LispFileNotFoundException(e));
-        }
-
+        this.errorManager = this.environment.getErrorManager();
         this.parser = new LispParser(this.environment.getInput(), this.environment.getInputName());
     }
 
@@ -72,40 +60,8 @@ public class LispInterpreter {
 
     protected void erasePrompt() {}
 
-    private LispException convertToLispException(RuntimeException e) {
-        return new LispException() {
-
-            private static final long serialVersionUID = 1L;
-
-            @Override
-            public String getMessage() {
-                return e.getMessage();
-            }
-        };
-    }
-
     protected void printFarewell() {
         environment.getOutput().println();
     }
 
-    public static class LispFileNotFoundException extends LispException {
-
-        private static final long serialVersionUID = 1L;
-        private String message;
-
-        public LispFileNotFoundException(FileNotFoundException e) {
-            this.message = e.getMessage();
-        }
-
-        @Override
-        public int getSeverity() {
-            return ErrorManager.CRITICAL_LEVEL;
-        }
-
-        @Override
-        public String getMessage() {
-            return message;
-        }
-    }
-
 }

src/interpreter/LispInterpreterBuilder.java

@@ -4,6 +4,8 @@ import java.io.*;
 
 public interface LispInterpreterBuilder {
 
+    void setInputName(String inputName);
+
     void setInput(InputStream inputStream);
 
     void setOutput(PrintStream outputStream);

src/interpreter/LispInterpreterBuilderImpl.java

@@ -13,23 +13,28 @@ public class LispInterpreterBuilderImpl implements LispInterpreterBuilder {
         return uniqueInstance;
     }
 
+    private String inputName;
     private InputStream inputStream;
     private PrintStream outputStream;
     private PrintStream errorOutputStream;
     private Runnable terminationFunction;
     private Runnable errorTerminationFunction;
     private RuntimeEnvironment environment;
-    private String fileName;
     private boolean isInteractive;
     private boolean isBuilt;
 
     private LispInterpreterBuilderImpl() {
         this.environment = RuntimeEnvironment.getInstance();
-        this.fileName = "";
+        this.inputName = "";
         this.isInteractive = true;
         this.isBuilt = false;
     }
 
+    @Override
+    public void setInputName(String inputName) {
+        this.inputName = inputName;
+    }
+
     @Override
     public void setInput(InputStream inputStream) {
         this.inputStream = inputStream;
@@ -58,7 +63,7 @@ public class LispInterpreterBuilderImpl implements LispInterpreterBuilder {
 
     @Override
     public void useFile(String fileName) {
-        this.fileName = fileName;
+        this.inputName = fileName;
         this.isInteractive = false;
     }
 
@@ -71,18 +76,40 @@ public class LispInterpreterBuilderImpl implements LispInterpreterBuilder {
     }
 
     private LispInterpreter buildInterpreter() {
-        environment.setInput(inputStream);
+        configureRuntimeEnvironment();
+        LispInterpreter lispInterpreter = createInterpreter();
+        isBuilt = true;
+
+        return lispInterpreter;
+    }
+
+    private void configureRuntimeEnvironment() {
+        ErrorManager errorManager = new ErrorManager();
+
         environment.setOutput(outputStream);
         environment.setErrorOutput(errorOutputStream);
         environment.setTerminationFunction(terminationFunction);
         environment.setErrorTerminationFunction(errorTerminationFunction);
+        environment.setErrorManager(errorManager);
+        configureInput(errorManager);
+    }
 
-        LispInterpreter lispInterpreter = isInteractive ? new InteractiveLispInterpreter()
-                                                        : new LispInterpreter(fileName);
+    private void configureInput(ErrorManager errorManager) {
+        environment.setInputName(inputName);
 
-        isBuilt = true;
+        try {
+            environment.setInput(getInputStream());
+        } catch (FileNotFoundException e) {
+            errorManager.generateError(new LispFileNotFoundException(e));
+        }
+    }
 
-        return lispInterpreter;
+    private InputStream getInputStream() throws FileNotFoundException {
+        return isInteractive ? inputStream : new FileInputStream(inputName);
+    }
+
+    private LispInterpreter createInterpreter() {
+        return isInteractive ? new InteractiveLispInterpreter() : new LispInterpreter();
     }
 
     public class InterpreterAlreadyBuiltException extends LispException {
@@ -100,4 +127,24 @@ public class LispInterpreterBuilderImpl implements LispInterpreterBuilder {
         }
     }
 
+    public static class LispFileNotFoundException extends LispException {
+
+        private static final long serialVersionUID = 1L;
+        private String message;
+
+        public LispFileNotFoundException(FileNotFoundException e) {
+            this.message = e.getMessage();
+        }
+
+        @Override
+        public int getSeverity() {
+            return ErrorManager.CRITICAL_LEVEL;
+        }
+
+        @Override
+        public String getMessage() {
+            return message;
+        }
+    }
+
 }

src/main/LispMain.java

@@ -13,16 +13,22 @@ public class LispMain {
 
     private static LispInterpreter buildInterpreter(String[] args) {
         LispInterpreterBuilder builder = LispInterpreterBuilderImpl.getInstance();
-        builder.setInput(System.in);
         builder.setOutput(System.out);
         builder.setErrorOutput(System.err);
         builder.setTerminationFunction(() -> System.exit(0));
         builder.setErrorTerminationFunction(() -> System.exit(1));
-
-        if (args.length > 0)
-            builder.useFile(args[0]);
+        configureInput(args, builder);
 
         return builder.build();
     }
 
+    private static void configureInput(String[] args, LispInterpreterBuilder builder) {
+        if (args.length > 0)
+            builder.useFile(args[0]);
+        else {
+            builder.setInputName("stdin");
+            builder.setInput(System.in);
+        }
+    }
+
 }

test/environment/RuntimeEnvironmentTester.java

@@ -6,6 +6,8 @@ import java.util.*;
 
 import org.junit.*;
 
+import error.ErrorManager;
+
 public class RuntimeEnvironmentTester {
 
     private static final String TERMINATED_SUCCESSFULLY = "TERMINATED_SUCCESSFULLY";
@@ -23,12 +25,18 @@ public class RuntimeEnvironmentTester {
         this.indicatorSet = new HashSet<>();
     }
 
+    @Test
+    public void assignInputName() {
+        this.environment.setInputName("test");
+
+        assertEquals("test", this.environment.getInputName());
+    }
+
     @Test
     public void assignInput() {
         this.environment.setInput(System.in);
 
         assertEquals(System.in, this.environment.getInput());
-        assertEquals(System.in.toString(), this.environment.getInputName());
     }
 
     @Test
@@ -61,4 +69,12 @@ public class RuntimeEnvironmentTester {
         assertTrue(indicatorSet.contains(TERMINATED_EXCEPTIONALLY));
     }
 
+    @Test
+    public void assignErrorManager() {
+        ErrorManager errorManager = new ErrorManager();
+        this.environment.setErrorManager(errorManager);
+
+        assertEquals(errorManager, this.environment.getErrorManager());
+    }
+
 }

test/function/builtin/LOADTester.java

@@ -1,6 +1,6 @@
 package function.builtin;
 
-import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.*;
 import static testutil.TestUtilities.*;
 
 import java.io.*;
@@ -15,12 +15,12 @@ public class LOADTester {
 
     private ByteArrayOutputStream outputStream;
 
-    private void assertPrinted(String expected) {
-        assertEquals(expected, outputStream.toString());
+    private void assertSomethingPrinted() {
+        assertTrue(outputStream.toByteArray().length > 0);
     }
 
     private void assertNothingPrinted() {
-        assertPrinted("");
+        assertTrue(outputStream.toByteArray().length == 0);
     }
 
     @Before
@@ -42,7 +42,7 @@ public class LOADTester {
         String input = "(load \"test/function/builtin/test-files/load-bad.lisp\")";
 
         assertSExpressionsMatch(Nil.getInstance(), evaluateString(input));
-        assertPrinted("LOAD: expression begins with ')' - line 1, column 1\n");
+        assertSomethingPrinted();
     }
 
     @Test
@@ -50,7 +50,7 @@ public class LOADTester {
         String input = "(load \"doesNotExist.lisp\")";
 
         assertSExpressionsMatch(Nil.getInstance(), evaluateString(input));
-        assertPrinted("LOAD: could not open 'doesNotExist.lisp'\n");
+        assertSomethingPrinted();
     }
 
     @Test(expected = BadArgumentTypeException.class)