您可以编写一个小程序来完成它。编译这样的东西,使用javac -target 1.3
:
public class Redirector
extends Applet {
@Override
public void start() {
String newURL;
Package pkg = Object.class.getPackage();
if (pkg.isCompatibleWith("1.7")) {
newURL = "java17.html";
} else if (pkg.isCompatibleWith("1.6")) {
newURL = "java16.html";
} else if (pkg.isCompatibleWith("1.5")) {
newURL = "java15.html";
} else if (pkg.isCompatibleWith("1.4")) {
newURL = "java14.html";
} else {
newURL = "java13.html";
}
try {
getAppletContext().showDocument(new URL(newURL));
} catch (MalformedURLException e) {
showStatus(e.toString());
}
}
}
如果你真的想让用户自己选择 Java 版本,你可以在你的小程序中为此创建 UI 元素:
public class Redirector
extends Applet
implements ActionListener {
private Choice list;
@Override
public void init() {
try {
EventQueue.invokeAndWait(new Runnable() {
public void run() {
list = new Choice();
list.add("1.7");
list.add("1.6");
list.add("1.5");
list.add("1.4");
list.add("1.3");
Button button = new Button("Launch");
button.addAtionListener(Redirector.this);
add(new Label("Java version:"));
add(list);
add(button);
}
});
} catch (InvocationTargetException e) {
throw new RuntimeException(e);
} catch (InterruptedException e) {
e.printStackTrace();
}
}
public void actionPeformed(ActionEvent event) {
String newURL;
String version = list.getSelectedItem();
if (version.equals("1.7")) {
newURL = "java17.html";
} else if (version.equals("1.6")) {
newURL = "java16.html";
} else if (version.equals("1.5")) {
newURL = "java15.html";
} else if (version.equals("1.4")) {
newURL = "java14.html";
} else {
newURL = "java13.html";
}
try {
getAppletContext().showDocument(new URL(newURL));
} catch (MalformedURLException e) {
showStatus(e.toString());
}
}
}