From 0bdce2e2b2c16cc9576e8d96c67ce2830c8b0afc Mon Sep 17 00:00:00 2001
From: Svjatoslav Agejenko <svjatoslav@svjatoslav.eu>
Date: Sun, 26 Jun 2022 01:54:59 +0300
Subject: [PATCH] Refactored exception dialog.

---
 .../commons/gui/dialog/ExceptionDialog.java   | 105 +++++++++---------
 1 file changed, 53 insertions(+), 52 deletions(-)

diff --git a/src/main/java/eu/svjatoslav/commons/gui/dialog/ExceptionDialog.java b/src/main/java/eu/svjatoslav/commons/gui/dialog/ExceptionDialog.java
index 2b86a6b..d56db29 100755
--- a/src/main/java/eu/svjatoslav/commons/gui/dialog/ExceptionDialog.java
+++ b/src/main/java/eu/svjatoslav/commons/gui/dialog/ExceptionDialog.java
@@ -7,6 +7,8 @@ package eu.svjatoslav.commons.gui.dialog;
 import javax.swing.*;
 import java.awt.*;
 
+import static javax.swing.BoxLayout.Y_AXIS;
+
 public class ExceptionDialog {
 
     public ExceptionDialog(final Exception exception) {
@@ -31,67 +33,66 @@ public class ExceptionDialog {
      * @param exception exception to show
      */
     public void showException(final Exception exception) {
+        final JPanel contentPanel = new JPanel(new BorderLayout());
+        contentPanel.add(getTopPanel(exception), BorderLayout.NORTH);
+        contentPanel.add(getStackTraceView(exception.getCause()), BorderLayout.CENTER);
 
         final JFrame frame = new JFrame("Exception occurred!");
-        final JPanel contentPanel = new JPanel(new BorderLayout());
-        final Throwable cause = exception.getCause();
-
-        // build top panel
-        {
-            final JPanel topPanel = new JPanel();
-            topPanel.setLayout(new BoxLayout(topPanel, BoxLayout.Y_AXIS));
-
-            // add exception type
-            final JLabel exceptionType = new JLabel("Exception type: "
-                    + exception.getClass().getCanonicalName());
-            topPanel.add(exceptionType);
-
-            // add error message
-            final JLabel message = new JLabel("Error message: "
-                    + exception.getMessage());
-            topPanel.add(message);
-
-            // add cause message
-            if (cause != null)
-                if (cause.getMessage() != null) {
-                    final JLabel message2 = new JLabel("Cause: "
-                            + cause.getMessage());
-                    topPanel.add(message2);
-                }
-
-            contentPanel.add(topPanel, BorderLayout.NORTH);
-        }
+        frame.getContentPane().add(contentPanel);
+        frame.setSize(800, 600);
+        frame.setVisible(true);
+        frame.setDefaultCloseOperation(WindowConstants.DISPOSE_ON_CLOSE);
+
+        centerFrameOnScreen(frame);
+    }
+
+    private void centerFrameOnScreen(JFrame frame) {
+        final Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
+        frame.setLocation(
+                (screenSize.width - frame.getWidth()) / 2,
+                (screenSize.height - frame.getHeight()) / 2);
+    }
 
-        // build stack trace view
-        {
-            final StringBuilder buffer = new StringBuilder();
+    private TextArea getStackTraceView(Throwable cause) {
+        final StringBuilder buffer = new StringBuilder();
 
+        if (cause != null) {
             // if cause is available, show original stack trace
-            if (cause != null) {
-                buffer.append("Stack trace:\n");
-                final StackTraceElement[] stackTrace = cause.getStackTrace();
-                for (final StackTraceElement stackTraceElement : stackTrace)
-                    buffer.append(stackTraceElement.toString() + "\n");
-            } else {
-                // otherwise show at least current stack trace
-                buffer.append("Stack trace from original cause is not available.\nShowing current stack trace instead:\n");
-
-                for (final StackTraceElement stackTraceElement : new Exception(
-                        "Stack trace").getStackTrace())
-                    buffer.append(stackTraceElement.toString() + "\n");
-            }
-
-            final TextArea textArea = new TextArea(buffer.toString());
-            contentPanel.add(textArea, BorderLayout.CENTER);
+            buffer.append("Stack trace:\n");
+            final StackTraceElement[] stackTrace = cause.getStackTrace();
+            enlistStackTraceElements(buffer, stackTrace);
+        } else {
+            // otherwise show at least current stack trace
+            buffer.append("Stack trace from original cause is not available.\n" +
+                    "Showing current stack trace instead:\n");
+            enlistStackTraceElements(buffer, new Exception("Stack trace").getStackTrace());
         }
 
-        // finalize frame
-        frame.getContentPane().add(contentPanel);
-        frame.setSize(800, 600);
-        frame.setVisible(true);
+        return new TextArea(buffer.toString());
+    }
+
+    private void enlistStackTraceElements(StringBuilder buffer, StackTraceElement[] stackTrace) {
+        for (final StackTraceElement stackTraceElement : stackTrace)
+            buffer.append(stackTraceElement.toString()).append("\n");
+    }
+
+    private JPanel getTopPanel(Exception exception) {
+
+        final JPanel topPanel = new JPanel();
+        topPanel.setLayout(new BoxLayout(topPanel, Y_AXIS));
+
+        // add exception type
+        topPanel.add(
+                new JLabel("Exception type: " + exception.getClass().getCanonicalName()));
 
-        // Thread.dumpStack();
+        // add error message
+        topPanel.add(new JLabel("Error message: " + exception.getMessage()));
 
+        // add cause message
+        Throwable cause = exception.getCause();
+        if (cause != null && cause.getMessage() != null)
+            topPanel.add(new JLabel("Cause: " + cause.getMessage()));
+        return topPanel;
     }
 
 }
-- 
2.20.1