git.gag.com Git - debian/openrocket/blob - src/net/sf/openrocket/startup/Startup.java

   1 package net.sf.openrocket.startup;
   2
   3 import java.awt.GraphicsEnvironment;
   4 import java.lang.reflect.InvocationTargetException;
   5 import java.lang.reflect.Method;
   6
   7 import javax.swing.JOptionPane;
   8
   9
  10 /**
  11  * A startup class that checks that a suitable JRE environment is being run.
  12  * If the environment is too old the execution is canceled, and if OpenJDK is being
  13  * used warns the user of problems and confirms whether to continue.
  14  * <p>
  15  * Note:  This class must be Java 1.4 compatible and calls the next class using
  16  * only reflection.
  17  *
  18  * @author Sampo Niskanen <sampo.niskanen@iki.fi>
  19  */
  20 public class Startup {
  21
  22         public static final String START_CLASS = "net.sf.openrocket.gui.main.BasicFrame";
  23
  24         public static final int REQUIRED_MAJOR_VERSION = 1;
  25         public static final int REQUIRED_MINOR_VERSION = 6;
  26
  27
  28         public static void main(String[] args) {
  29
  30                 checkVersion();
  31                 checkHead();
  32                 checkOpenJDK();
  33
  34                 // Load and execute START_CLASS
  35                 try {
  36
  37                         Class cls = Class.forName(START_CLASS);
  38                         Method m = cls.getMethod("main", String[].class);
  39                         m.invoke(null, new Object[] { args });
  40
  41                 } catch (ClassNotFoundException e) {
  42                         e.printStackTrace();
  43                         error("Error starting main class!", "Please report a bug.");
  44                 } catch (NoSuchMethodException e) {
  45                         e.printStackTrace();
  46                         error("Error starting main class!", "Please report a bug.");
  47                 } catch (InvocationTargetException e) {
  48                         e.printStackTrace();
  49                         error("Error starting main class!", "Please report a bug.");
  50                 } catch (IllegalAccessException e) {
  51                         e.printStackTrace();
  52                         error("Error starting main class!", "Please report a bug.");
  53                 }
  54
  55         }
  56
  57
  58         /**
  59          * Check that the JRE version is high enough.
  60          */
  61         private static void checkVersion() {
  62                 String[] version = System.getProperty("java.specification.version", "").split("\\.");
  63
  64                 String jreName = System.getProperty("java.vm.name", "(unknown)");
  65                 String jreVersion = System.getProperty("java.runtime.version", "(unknown)");
  66                 String jreVendor = System.getProperty("java.vendor", "(unknown)");
  67
  68                 int major, minor;
  69
  70                 try {
  71                         major = Integer.parseInt(version[0]);
  72                         minor = Integer.parseInt(version[1]);
  73
  74                         if (major < REQUIRED_MAJOR_VERSION ||
  75                                         (major == REQUIRED_MAJOR_VERSION && minor < REQUIRED_MINOR_VERSION)) {
  76                                 error("Java SE version 6 is required to run OpenRocket.",
  77                                                 "You are currently running " + jreName + " version " +
  78                                                 jreVersion + " by " + jreVendor);
  79                         }
  80
  81                 } catch (RuntimeException e) {
  82
  83                         confirm("The Java version in use could not be detected.",
  84                                         "OpenRocket requires at least Java SE 6.",
  85                                         "Continue anyway?");
  86
  87                 }
  88
  89         }
  90
  91
  92         /**
  93          * Check that the JRE is not running headless.
  94          */
  95         private static void checkHead() {
  96
  97                 if (GraphicsEnvironment.isHeadless()) {
  98                         System.err.println();
  99                         System.err.println("OpenRocket cannot currently be run without the graphical " +
 100                                         "user interface.");
 101                         System.err.println();
 102                         System.exit(1);
 103                 }
 104
 105         }
 106
 107
 108         /**
 109          * Check whether OpenJDK is being used, and if it is warn the user about
 110          * problems and confirm whether to continue.
 111          */
 112         private static void checkOpenJDK() {
 113
 114                 if (System.getProperty("java.runtime.name", "").toLowerCase().indexOf("icedtea")>=0 ||
 115                                 System.getProperty("java.vm.name", "").toLowerCase().indexOf("openjdk")>=0) {
 116
 117                         String jreName = System.getProperty("java.vm.name", "(unknown)");
 118                         String jreVersion = System.getProperty("java.runtime.version", "(unknown)");
 119                         String jreVendor = System.getProperty("java.vendor", "(unknown)");
 120
 121                         confirm("OpenJDK is known to have problems running OpenRocket.",
 122                                         " ",
 123                                         "You are currently running " + jreName + " version " +
 124                                         jreVersion + " by " + jreVendor,
 125                                         "Do you want to continue?");
 126
 127                 }
 128         }
 129
 130
 131
 132
 133         /**
 134          * Presents an error message to the user and exits the application.
 135          *
 136          * @param message       an array of messages to present.
 137          */
 138         private static void error(String ... message) {
 139
 140                 System.err.println();
 141                 System.err.println("Error starting OpenRocket:");
 142                 System.err.println();
 143                 for (int i=0; i < message.length; i++) {
 144                         System.err.println(message[i]);
 145                 }
 146                 System.err.println();
 147
 148
 149                 if (!GraphicsEnvironment.isHeadless()) {
 150
 151                         JOptionPane.showMessageDialog(null, message, "Error starting OpenRocket",
 152                                         JOptionPane.ERROR_MESSAGE);
 153
 154                 }
 155
 156                 System.exit(1);
 157         }
 158
 159
 160         /**
 161          * Presents the user with a message dialog and asks whether to continue.
 162          * If the user does not select "Yes" the the application exits.
 163          *
 164          * @param message       the message Strings to show.
 165          */
 166         private static void confirm(String ... message) {
 167
 168                 if (!GraphicsEnvironment.isHeadless()) {
 169
 170                         if (JOptionPane.showConfirmDialog(null, message, "Error starting OpenRocket",
 171                                         JOptionPane.YES_NO_OPTION) != JOptionPane.YES_OPTION) {
 172                                 System.exit(1);
 173                         }
 174
 175                 }
 176
 177         }
 178
 179
 180 }