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object Test1 {
class Foo {
@remote
def foo: Unit = ()
}
def run {
val method = classOf[Foo].getMethod("foo", Array())
method.getExceptionTypes foreach Console.println
}
}
object Test2 {
import java.io.{BufferedReader,FileReader, IOException}
class Reader(fname: String) {
private val in = new BufferedReader(new FileReader(fname))
@throws(classOf[IOException])
def read() = in.read()
}
def run {
val method = classOf[Reader].getMethod("read", Array())
method.getExceptionTypes foreach Console.println
}
}
/* Java:
public class Main {
@Deprecated
public void foo() {}
public static void main(String[] args) throws Exception {
Method method = Class.forName("test.Main").getMethod("foo", new Class[]{});
Annotation annotation = method.getAnnotation(Deprecated.class);
System.out.println(annotation); // @java.lang.Deprecated()
}
}
*/
object Test3 {
import java.lang.Deprecated
class Foo {
@Deprecated
def foo: Unit = ()
}
def run {
val method = classOf[Foo].getMethod("foo", Array())
val annotation = method.getAnnotation(classOf[Deprecated])
Console.println(annotation)
}
}
/* Java:
@Retention(value=RetentionPolicy.RUNTIME)
@interface Source {
public String url();
public String mail();
}
@Source(url="http://scala.epfl.ch", mail="scala@lists.epfl.ch")
class Foo {}
public class Main {
public static void main(String[] args) throws Exception {
Class clazz = Class.forName("test.Foo");
Annotation[] annotations = clazz.getAnnotations();
for (int i = 0; i < annotations.length; i++)
System.out.println(annotations[i]);
// @test.Main$Source(url=http://scala-lang.org, mail=scala@lists.epfl.ch)
}
}
*/
object Test4 {
import test.SourceAnnotation // defined in SourceAnnotation.java
@SourceAnnotation{val value = "http://scala-lang.org",
val mails = Array("scala@lists.epfl.ch", "scala-lounge@lists.epfl.ch")}
class Foo1
@SourceAnnotation("http://bloodsuckers.com") { val mails = Array("you@bloodsuckers.com") }
class Foo2
@SourceAnnotation("http://bloodsuckers.com")
class Foo3
class Foo4 {
@SourceAnnotation("file:///dev/null")
val x = 1
@SourceAnnotation("file:///dev/zero")
def bar: Int = 0
}
def run {
import java.lang.annotation.Annotation
import java.lang.reflect.AnnotatedElement
def printSourceAnnotations(target: AnnotatedElement) {
//print SourceAnnotation in a predefined way to insure
// against difference in the JVMs (e.g. Sun's vs IBM's)
def printSourceAnnotation(a: Annotation) {
val ann = a.asInstanceOf[SourceAnnotation]
Console.println("@test.SourceAnnotation(mails=" + ann.mails.deepMkString("{", ",", "}") +
", value=" + ann.value + ")")
}
val anns = target.getAnnotations()
anns foreach printSourceAnnotation
if (anns.length > 0) {
Console.println(target)
Console.println
}
}
printSourceAnnotations(classOf[Foo1])
printSourceAnnotations(classOf[Foo2])
printSourceAnnotations(classOf[Foo3])
classOf[Foo4].getDeclaredFields foreach printSourceAnnotations
classOf[Foo4].getDeclaredMethods foreach printSourceAnnotations
}
}
object Test5 {
import scala.reflect.BeanProperty
class Count {
// we use "Integer" instead of "Int" because of Java reflection
@BeanProperty
private var count: Integer = 0
private val getter =
getClass().getMethod("getCount", Array[java.lang.Class]())
private val setter =
getClass().getMethod("setCount", Array[java.lang.Class](classOf[Integer]))
def get = getter.invoke(this, Array()).asInstanceOf[Integer].intValue
def set(n: Int) = setter.invoke(this, Array(new Integer(n)))
}
def run {
val count = new Count
Console.println(count.get)
count.set(99)
Console.println(count.get)
}
}
object Test {
def main(args: Array[String]): Unit = {
Test1.run
Test2.run
Test3.run // requires the use of -target:jvm-1.5
Test4.run
Test5.run
}
}
|
