Issue#305: Restore terminal on close()

Previously we had to wait for JVM to exit and the shutdown hook to trigger. This also removes the shutdown hook if the terminal is closed manually.

src/main/java/com/googlecode/lanterna/terminal/ansi/UnixLikeTTYTerminal.java

@@ -75,16 +75,16 @@ protected UnixLikeTTYTerminal(
         this.ttyDev = ttyDev;
 
         // Take ownership of the terminal
-        realAquire();
+        realAcquire();
     }
 
     @Override
-    protected void aquire() throws IOException {
+    protected void acquire() throws IOException {
         // Hack!
     }
 
-    private void realAquire() throws IOException {
-        super.aquire();
+    private void realAcquire() throws IOException {
+        super.acquire();
     }
 
     @Override

src/main/java/com/googlecode/lanterna/terminal/ansi/UnixLikeTerminal.java

@@ -48,20 +48,29 @@ public enum CtrlCBehaviour {
 
     private final CtrlCBehaviour terminalCtrlCBehaviour;
     private final boolean catchSpecialCharacters;
+    private final Thread shutdownHook;
+    private boolean acquired;
 
     protected UnixLikeTerminal(InputStream terminalInput,
                             OutputStream terminalOutput,
                             Charset terminalCharset,
                             CtrlCBehaviour terminalCtrlCBehaviour) throws IOException {
 
         super(terminalInput, terminalOutput, terminalCharset);
+        this.acquired = false;
 
         String catchSpecialCharactersPropValue = System.getProperty(
                 "com.googlecode.lanterna.terminal.UnixTerminal.catchSpecialCharacters",
                 "");
         this.catchSpecialCharacters = !"false".equals(catchSpecialCharactersPropValue.trim().toLowerCase());
         this.terminalCtrlCBehaviour = terminalCtrlCBehaviour;
-        aquire();
+        shutdownHook = new Thread("Lanterna STTY restore") {
+            @Override
+            public void run() {
+                exitPrivateModeAndRestoreState();
+            }
+        };
+        acquire();
     }
 
     /**
@@ -70,7 +79,7 @@ protected UnixLikeTerminal(InputStream terminalInput,
      * of any end-user class extending from {@link UnixLikeTerminal}
      * @throws IOException If there was an I/O error
      */
-    protected void aquire() throws IOException {
+    protected void acquire() throws IOException {
         //Make sure to set an initial size
         onResized(80, 24);
 
@@ -92,9 +101,17 @@ public void run() {
                 }
             }
         });
-        setupShutdownHook();
+        Runtime.getRuntime().addShutdownHook(shutdownHook);
+        acquired = true;
     }
 
+    @Override
+    public void close() throws IOException {
+        exitPrivateModeAndRestoreState();
+        Runtime.getRuntime().removeShutdownHook(shutdownHook);
+        acquired = false;
+        super.close();
+    }
 
     @Override
     public KeyStroke pollInput() throws IOException {
@@ -188,24 +205,21 @@ private void isCtrlC(KeyStroke key) throws IOException {
         }
     }
 
-    private void setupShutdownHook() {
-        Runtime.getRuntime().addShutdownHook(new Thread("Lanterna STTY restore") {
-            @Override
-            public void run() {
-                try {
-                    if (isInPrivateMode()) {
-                        exitPrivateMode();
-                    }
-                }
-                catch(IOException ignored) {}
-                catch(IllegalStateException ignored) {} // still possible!
-
-                try {
-                    restoreTerminalSettingsAndKeyStrokeSignals();
-                }
-                catch(IOException ignored) {}
+    private void exitPrivateModeAndRestoreState() {
+        if(!acquired) {
+            return;
+        }
+        try {
+            if (isInPrivateMode()) {
+                exitPrivateMode();
             }
-        });
-    }
+        }
+        catch(IOException ignored) {}
+        catch(IllegalStateException ignored) {} // still possible!
 
+        try {
+            restoreTerminalSettingsAndKeyStrokeSignals();
+        }
+        catch(IOException ignored) {}
+    }
 }

src/test/java/com/googlecode/lanterna/issue/Issue305.java

@@ -0,0 +1,54 @@
+package com.googlecode.lanterna.issue;
+
+import com.googlecode.lanterna.terminal.DefaultTerminalFactory;
+import com.googlecode.lanterna.terminal.Terminal;
+
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStreamReader;
+
+/**
+ * Created by martin on 2017-04-15.
+ */
+public class Issue305 {
+    /**
+     * @param args the command line arguments
+     */
+    public static void main(String[] args) throws IOException, InterruptedException{
+        Terminal terminal = new DefaultTerminalFactory().createTerminal();
+        System.out.println("Class: " + terminal.getClass());
+
+        terminal.close();
+
+        BufferedReader br = null;
+        try {
+            br = new BufferedReader(new InputStreamReader(System.in));
+
+            while (true) {
+
+                System.out.print("Enter something: ");
+                String input = br.readLine();
+
+                if ("q".equals(input)) {
+                    System.out.println("Exit!");
+                    System.exit(0);
+                }
+
+                System.out.println("input : " + input);
+                System.out.println("-----------\n");
+            }
+
+        } catch (IOException e) {
+            e.printStackTrace();
+        } finally {
+            if (br != null) {
+                try {
+                    br.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+
+    }
+}