Добавлен обработчик консольного ввода JLine

Author: aNNiMON

build.gradle

@@ -93,6 +93,7 @@ dependencies {
     }
     compile 'org.json:json:20160212'
     compile 'org.yaml:snakeyaml:1.17'
+    compile 'jline:jline:2.14.5'
 
     testCompile 'junit:junit:4.12'
     testCompile 'org.openjdk.jmh:jmh-core:1.13'

src/main/java/com/annimon/ownlang/utils/Repl.java

@@ -13,11 +13,14 @@
 import com.annimon.ownlang.parser.ast.BlockStatement;
 import com.annimon.ownlang.parser.ast.Statement;
 import com.annimon.ownlang.parser.visitors.PrintVisitor;
+import com.annimon.ownlang.utils.repl.JLineConsole;
+import com.annimon.ownlang.utils.repl.ReplConsole;
+import com.annimon.ownlang.utils.repl.SystemConsole;
+import java.io.IOException;
 import java.util.ArrayList;
 import java.util.List;
 import java.util.Locale;
 import java.util.Map;
-import java.util.Scanner;
 import java.util.stream.Collectors;
 
 public final class Repl {
@@ -36,14 +39,13 @@ public static void main(String[] args) {
 
         final BlockStatement history = new BlockStatement();
         final StringBuilder buffer = new StringBuilder();
-        final Scanner scanner = new Scanner(System.in);
+        final ReplConsole console = initReplConsole();
         while (true) {
-            System.out.print((buffer.length() == 0) ? "\n> " : "  ");
+            console.setPrompt((buffer.length() == 0) ? "\n> " : "  ");
 
-            if (!scanner.hasNextLine()) break;
+            final String line = console.readLine();
+            if (line == null || EXIT.equalsIgnoreCase(line)) break;
 
-            final String line = scanner.nextLine();
-            if (EXIT.equalsIgnoreCase(line)) break;
             switch (line.toLowerCase(Locale.ENGLISH)) {
                 case RESET:
                     buffer.setLength(0);
@@ -84,7 +86,15 @@ public static void main(String[] args) {
             }
             buffer.setLength(0);
         }
-        scanner.close();
+        console.close();
+    }
+
+    private static ReplConsole initReplConsole() {
+        try {
+            return new JLineConsole();
+        } catch (IOException ioe) {
+            return new SystemConsole();
+        }
     }
 
     private static void printHelp(boolean full) {

src/main/java/com/annimon/ownlang/utils/repl/JLineConsole.java

@@ -0,0 +1,41 @@
+package com.annimon.ownlang.utils.repl;
+
+import java.io.IOException;
+import jline.TerminalFactory;
+import jline.console.ConsoleReader;
+
+public class JLineConsole implements ReplConsole {
+
+    private final ConsoleReader console;
+
+    public JLineConsole() throws IOException {
+        console = new ConsoleReader();
+    }
+
+    public ConsoleReader getConsole() {
+        return console;
+    }
+
+    @Override
+    public void setPrompt(String prompt) {
+        console.setPrompt(prompt);
+    }
+
+    @Override
+    public String readLine() {
+        try {
+            return console.readLine();
+        } catch (IOException ex) {
+            return null;
+        }
+    }
+
+    @Override
+    public void close() {
+        try {
+            TerminalFactory.get().restore();
+        } catch (Exception ignored) {
+        }
+    }
+
+}

src/main/java/com/annimon/ownlang/utils/repl/ReplConsole.java

@@ -0,0 +1,10 @@
+package com.annimon.ownlang.utils.repl;
+
+public interface ReplConsole {
+
+    void setPrompt(String prompt);
+
+    String readLine();
+
+    void close();
+}

src/main/java/com/annimon/ownlang/utils/repl/SystemConsole.java

@@ -0,0 +1,31 @@
+package com.annimon.ownlang.utils.repl;
+
+import java.util.Scanner;
+
+public class SystemConsole implements ReplConsole {
+
+    private final Scanner scanner;
+
+    public SystemConsole() {
+        scanner = new Scanner(System.in);
+    }
+
+    @Override
+    public void setPrompt(String prompt) {
+        System.out.print(prompt);
+    }
+
+    @Override
+    public String readLine() {
+        if (!scanner.hasNextLine()) {
+            return null;
+        }
+        return scanner.nextLine();
+    }
+
+    @Override
+    public void close() {
+        scanner.close();
+    }
+
+}