/**
* Creates an <code>ComponentUI</code> implementation for the specified component. In other words
* create the look and feel specific delegate object for <code>target</code>. This is done in two
* steps:
*
* <ul>
* <li>Look up the name of the <code>ComponentUI</code> implementation class under the value
* returned by <code>target.getUIClassID()</code>.
* <li>Use the implementation classes static <code>createUI()</code> method to construct a look
* and feel delegate.
* </ul>
*
* @param target the <code>JComponent</code> which needs a UI
* @return the <code>ComponentUI</code> object
*/
public ComponentUI getUI(JComponent target) {
Object cl = get("ClassLoader");
ClassLoader uiClassLoader =
(cl != null) ? (ClassLoader) cl : target.getClass().getClassLoader();
Class<? extends ComponentUI> uiClass = getUIClass(target.getUIClassID(), uiClassLoader);
Object uiObject = null;
if (uiClass == null) {
getUIError("no ComponentUI class for: " + target);
} else {
try {
Method m = (Method) get(uiClass);
if (m == null) {
m = uiClass.getMethod("createUI", new Class[] {JComponent.class});
put(uiClass, m);
}
uiObject = MethodUtil.invoke(m, null, new Object[] {target});
} catch (NoSuchMethodException e) {
getUIError("static createUI() method not found in " + uiClass);
} catch (Exception e) {
getUIError("createUI() failed for " + target + " " + e);
}
}
return (ComponentUI) uiObject;
}
private static <T> T convertFromString(String s, OpenType<T> openType) {
Class<T> c;
try {
ReflectUtil.checkPackageAccess(openType.safeGetClassName());
c = cast(Class.forName(openType.safeGetClassName()));
} catch (ClassNotFoundException e) {
throw new NoClassDefFoundError(e.toString()); // can't happen
}
// Look for: public static T valueOf(String)
Method valueOf;
try {
// It is safe to call this plain Class.getMethod because the class "c"
// was checked before by ReflectUtil.checkPackageAccess(openType.safeGetClassName());
valueOf = c.getMethod("valueOf", String.class);
if (!Modifier.isStatic(valueOf.getModifiers()) || valueOf.getReturnType() != c)
valueOf = null;
} catch (NoSuchMethodException e) {
valueOf = null;
}
if (valueOf != null) {
try {
return c.cast(MethodUtil.invoke(valueOf, null, new Object[] {s}));
} catch (Exception e) {
final String msg = "Could not convert \"" + s + "\" using method: " + valueOf;
throw new IllegalArgumentException(msg, e);
}
}
// Look for: public T(String)
Constructor<T> con;
try {
// It is safe to call this plain Class.getConstructor because the class "c"
// was checked before by ReflectUtil.checkPackageAccess(openType.safeGetClassName());
con = c.getConstructor(String.class);
} catch (NoSuchMethodException e) {
con = null;
}
if (con != null) {
try {
return con.newInstance(s);
} catch (Exception e) {
final String msg = "Could not convert \"" + s + "\" using constructor: " + con;
throw new IllegalArgumentException(msg, e);
}
}
throw new IllegalArgumentException(
"Don't know how to convert " + "string to " + openType.getTypeName());
}