fix broken links on some desktop

Introduce OSHelper class that should be used when trying to detect the type of
OS we are on. This is now used when deciding the path to save the config to
and when trying to execute the fallback command if opening the link via
java's desktop API fails.

3 files changed, 59 insertions, 26 deletions

diff --git a/dozentenmodul/src/main/java/org/openslx/dozmod/Config.java b/dozentenmodul/src/main/java/org/openslx/dozmod/Config.java
index ba21544d..7a3db999 100755
--- a/dozentenmodul/src/main/java/org/openslx/dozmod/Config.java
+++ b/dozentenmodul/src/main/java/org/openslx/dozmod/Config.java
@@ -10,6 +10,7 @@ import java.util.Properties;
 
 import org.apache.log4j.Logger;
 import org.openslx.dozmod.gui.window.DisclaimerWindow;
+import org.openslx.dozmod.util.OSHelper;
 import org.openslx.util.QuickTimer;
 import org.openslx.util.QuickTimer.Task;
 import org.openslx.util.Util;
@@ -69,7 +70,7 @@ public class Config {
 		// Determine OS
 		String osName = System.getProperty("os.name").toLowerCase();
 		LOGGER.info("Machine's OS: " + osName);
-		if (osName.contains("windows")) {
+		if (OSHelper.isWindows()) {
 			// Windows machine. Use the environment variable 'APPDATA' which
 			// should point to a path similar to:
 			//		C:\Users\<user>\AppData\Roaming
@@ -81,7 +82,7 @@ public class Config {
 				LOGGER.warn("APPDATA is empty.");
 				configPath = System.getProperty("user.home") + "\\AppData\\Roaming";
 			}
-		} else if (osName.contains("linux")) {
+		} else if (OSHelper.isLinux()) {
 			configPath = System.getProperty("user.home") + "/.config";
 		}
 		if (configPath == null || configPath.isEmpty()) {
diff --git a/dozentenmodul/src/main/java/org/openslx/dozmod/util/OSHelper.java b/dozentenmodul/src/main/java/org/openslx/dozmod/util/OSHelper.java
new file mode 100644
index 00000000..a3860dfa
--- /dev/null
+++ b/dozentenmodul/src/main/java/org/openslx/dozmod/util/OSHelper.java
@@ -0,0 +1,13 @@
+package org.openslx.dozmod.util;
+
+public final class OSHelper {
+
+	public final static String osName = System.getProperty("os.name").toLowerCase();
+
+	public final static boolean isWindows() {
+		return osName.contains("windows");
+	}
+	public final static boolean isLinux() {
+		return osName.contains("linux");
+	}
+}
diff --git a/dozentenmodul/src/main/java/org/openslx/dozmod/util/OpenLinks.java b/dozentenmodul/src/main/java/org/openslx/dozmod/util/OpenLinks.java
index 2a181a34..dc34922b 100644
--- a/dozentenmodul/src/main/java/org/openslx/dozmod/util/OpenLinks.java
+++ b/dozentenmodul/src/main/java/org/openslx/dozmod/util/OpenLinks.java
@@ -2,6 +2,7 @@ package org.openslx.dozmod.util;
 
 import java.awt.Desktop;
 import java.io.File;
+import java.io.IOException;
 import java.net.URI;
 import java.net.URLEncoder;
 
@@ -41,7 +42,7 @@ public class OpenLinks {
 	public static boolean openWebpage(Link location) {
 		return openWebpageUri(location.uri);
 	}
-	
+
 	public static boolean openWebpageUri(URI uri) {
 		if (desktop != null && desktop.isSupported(Desktop.Action.BROWSE)) {
 			try {
@@ -51,7 +52,7 @@ public class OpenLinks {
 				LOGGER.error("Got exception in openWebpage: ", e);
 			}
 		}
-		return false;
+		return fallbackExec(uri.toString());
 	}
 
 	public static boolean openLocal(File path) {
@@ -61,17 +62,7 @@ public class OpenLinks {
 		} catch (Exception e) {
 			LOGGER.error("Got exception in openLocal: ", e);
 		}
-		try {
-			int exitCode = Runtime.getRuntime()
-					.exec(new String[] { "xdg-open", path.getAbsolutePath() })
-					.waitFor();
-			if (exitCode == 0)
-				return true;
-			LOGGER.error("xdg-open returned " + exitCode);
-		} catch (Exception e) {
-			LOGGER.error("xdg-open fallback failed", e);
-		}
-		return false;
+		return fallbackExec(path.getAbsolutePath());
 	}
 
 	/**
@@ -83,20 +74,48 @@ public class OpenLinks {
 	 * @return false on not-success
 	 */
 	public static boolean sendMail(String address, String subject) {
-		if (desktop != null && desktop.isSupported(Desktop.Action.MAIL)) {
-			try {
-				if (subject != null) {
-					desktop.mail(new URI("mailto:" + address + "?subject="
-							+ URLEncoder.encode(subject, "UTF-8")));
-				} else {
-					desktop.mail(new URI("mailto:" + address));
-				}
+		URI mailToUri = null;
+		try {
+			if (subject != null) {
+				mailToUri = new URI("mailto:" + address + "?subject=" + URLEncoder.encode(subject, "UTF-8"));
+			} else {
+				mailToUri = new URI("mailto:" + address);
+			}
+			if (desktop != null && desktop.isSupported(Desktop.Action.MAIL)) {
+				desktop.mail(mailToUri);
 				return true;
-			} catch (Exception e) {
-				LOGGER.error("Got exception in sendMail: ", e);
 			}
+		} catch (Exception e) {
+			LOGGER.error("Got exception in sendMail: ", e);
 		}
-		return false;
+		return mailToUri != null && fallbackExec(mailToUri.toString());
 	}
 
+	/**
+	 * Opens the given link using the system's preferred application. This makes
+	 * use of OSHelper to create a OS-dependent command to execute.
+	 *
+	 * @param link to open
+	 * @return true if the external command executed successfully, false
+	 *         otherwise.
+	 */
+	public static boolean fallbackExec(String link) {
+		String[] execCommand;
+		if (OSHelper.isLinux()) {
+			execCommand = new String[] { "xdg-open", link };
+		} else if (OSHelper.isWindows()) {
+			execCommand = new String[] { "cmd.exe", "/c", "start", link };
+		} else {
+			LOGGER.error("Could not set command for unknown operating system: " + OSHelper.osName);
+			return false;
+		}
+		int exitCode = -1;
+		try {
+			exitCode = Runtime.getRuntime().exec(execCommand).waitFor();
+		} catch (InterruptedException | IOException e) {
+			LOGGER.debug("Failed to execute: " + execCommand + "\nTrace: ", e);
+			return false;
+		}
+		return exitCode == 0;
+	}
 }