Fix parsing of Java version strings

.gitattributes

@@ -268,6 +268,7 @@ forge-core/src/main/java/forge/util/MyRandom.java svneol=native#text/plain
 forge-core/src/main/java/forge/util/NameGenerator.java -text
 forge-core/src/main/java/forge/util/PredicateString.java -text
 forge-core/src/main/java/forge/util/ReflectionUtil.java -text
+forge-core/src/main/java/forge/util/RuntimeVersion.java -text
 forge-core/src/main/java/forge/util/Settable.java -text
 forge-core/src/main/java/forge/util/TextUtil.java -text
 forge-core/src/main/java/forge/util/ThreadUtil.java -text

forge-core/src/main/java/forge/util/RuntimeVersion.java

@@ -0,0 +1,124 @@
+package forge.util;
+
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+public class RuntimeVersion {
+
+	private static Pattern versionNumberPattern = Pattern.compile("([1-9][0-9]*((\\.0)*\\.[1-9][0-9]*)*)");
+	private static Pattern preReleasePattern = Pattern.compile("([a-zA-Z0-9]+)");
+	private static Pattern buildNumberPattern = Pattern.compile("(0|[1-9][0-9]*)");
+	private static Pattern buildInformationPattern = Pattern.compile("([-a-zA-Z0-9.]+)");
+
+	private static Pattern versionStringPattern1 = Pattern.compile(versionNumberPattern + "(-" + preReleasePattern + ")?\\+" + buildNumberPattern + "(-" + buildInformationPattern + ")?");
+	private static Pattern versionStringPattern2 = Pattern.compile(versionNumberPattern + "-" + preReleasePattern + "(-" + buildInformationPattern + ")?");
+	private static Pattern versionStringPattern3 = Pattern.compile(versionNumberPattern + "(+-" + buildInformationPattern + ")?");
+	private static Pattern versionStringPattern4 = Pattern.compile(versionNumberPattern + "(-" + preReleasePattern + ")?");
+
+	private int major;
+	private int minor;
+	private int securityLevel;
+
+	private String preReleaseIdentifier;
+	private int buildNumber;
+	private String buildInformation;
+
+	@SuppressWarnings("ResultOfMethodCallIgnored")
+	private RuntimeVersion(final String versionString) {
+
+		Matcher matcher = versionNumberPattern.matcher(versionString);
+
+		if (!matcher.find()) {
+			throw new IllegalArgumentException("Improperly formatted version string provided: " + versionString);
+		}
+
+		String[] versionNumbers = matcher.group().split("\\.");
+
+		if (versionNumbers.length >= 1) {
+			major = Integer.parseInt(versionNumbers[0]);
+		}
+
+		if (versionNumbers.length >= 2) {
+			minor = Integer.parseInt(versionNumbers[1]);
+		}
+
+		if (versionNumbers.length >= 3) {
+			securityLevel = Integer.parseInt(versionNumbers[2]);
+		}
+
+		if (versionStringPattern1.matcher(versionString).find()) {
+
+			Matcher infoMatcher = preReleasePattern.matcher(versionString);
+			if (infoMatcher.find()) {
+				preReleaseIdentifier = infoMatcher.group();
+			}
+
+			infoMatcher = buildNumberPattern.matcher(versionString);
+			infoMatcher.find();
+			buildNumber = Integer.parseInt(infoMatcher.group());
+
+			infoMatcher = buildInformationPattern.matcher(versionString);
+			if (infoMatcher.find()) {
+				buildInformation = infoMatcher.group();
+			}
+
+		} else if (versionStringPattern2.matcher(versionString).find()) {
+
+			Matcher infoMatcher = preReleasePattern.matcher(versionString);
+			infoMatcher.find();
+			preReleaseIdentifier = infoMatcher.group();
+
+			infoMatcher = buildInformationPattern.matcher(versionString);
+			if (infoMatcher.find()) {
+				buildInformation = infoMatcher.group();
+			}
+
+		} else if (versionStringPattern3.matcher(versionString).find()) {
+
+			Matcher infoMatcher = buildInformationPattern.matcher(versionString);
+			if (infoMatcher.find()) {
+				buildInformation = infoMatcher.group();
+			}
+
+		} else if (versionStringPattern4.matcher(versionString).find()) {
+
+			Matcher infoMatcher = preReleasePattern.matcher(versionString);
+			if (infoMatcher.find()) {
+				preReleaseIdentifier = infoMatcher.group();
+			}
+
+		} else {
+			throw new IllegalArgumentException("Improperly formatted version string provided: " + versionString);
+		}
+
+	}
+
+	public static RuntimeVersion of(final String versionString) {
+		return new RuntimeVersion(versionString);
+	}
+
+	public int getMajor() {
+		return major;
+	}
+
+	public int getMinor() {
+		return minor;
+	}
+
+	public int getSecurityLevel() {
+		return securityLevel;
+	}
+
+	public String getPreReleaseIdentifier() {
+		return preReleaseIdentifier;
+	}
+
+	public int getBuildNumber() {
+		return buildNumber;
+	}
+
+	public String getBuildInformation() {
+		return buildInformation;
+	}
+
+}

forge-gui-desktop/src/main/java/forge/screens/home/settings/VSubmenuDownloaders.java

@@ -12,6 +12,7 @@ import forge.screens.home.IVSubmenu;
 import forge.screens.home.VHomeUI;
 import forge.toolbox.*;
 import forge.util.FileUtil;
+import forge.util.RuntimeVersion;
 import net.miginfocom.swing.MigLayout;
 
 import javax.swing.*;
@@ -107,12 +108,9 @@ public enum VSubmenuDownloaders implements IVSubmenu<CSubmenuDownloaders> {
 
     private boolean javaRecentEnough() {
 
-        String fullJavaVersion = System.getProperty("java.version");
+        RuntimeVersion javaVersion = RuntimeVersion.of(System.getProperty("java.version"));
 
-        int majorVersion = Integer.parseInt(fullJavaVersion.split("_")[0].split("\\.")[1]);
+        return javaVersion.getMajor() > 8 || (javaVersion.getMajor() == 8 && javaVersion.getSecurityLevel() >= 101);
-        int minorVersion = Integer.parseInt(fullJavaVersion.split("_")[1]);
-
-        return majorVersion > 8 || (majorVersion == 8 && minorVersion >= 101);
 
     }
 
@@ -274,4 +272,5 @@ public enum VSubmenuDownloaders implements IVSubmenu<CSubmenuDownloaders> {
         return new FLabel.Builder().fontAlign(SwingConstants.CENTER)
                 .text(label).fontStyle(Font.ITALIC).build();
     }
+
 }