j2k: flatten test cases and testData directory structure

Move j2k/test/tests -> j2k/tests, j2k/test/testData -> j2k/testData

j2k/testData/JavaApi.java

@@ -0,0 +1,64 @@
+package javaApi;
+
+import org.jetbrains.annotations.Nullable;
+import java.util.Set;
+
+public @interface Anon1 {
+    String[] value();
+    String[] stringArray();
+    int[] intArray();
+    String string();
+}
+
+public @interface Anon2 {
+    String value();
+    int intValue();
+    char charValue();
+}
+
+public @interface Anon3 {
+    E e();
+    String[] stringArray();
+    String[] value();
+}
+
+public @interface Anon4 {
+    String[] value();
+}
+
+public @interface Anon5 {
+    int value();
+}
+
+public @interface Anon6 {
+    String[] value();
+    int intValue() default 10;
+}
+
+public @interface Anon7 {
+    Class[] value();
+}
+
+public @interface Anon8 {
+    Class[] classes();
+}
+
+public enum E {
+    A, B, C
+}
+
+public class Base {
+    public @Nullable String foo(@Nullable String s) { return s; }
+}
+
+public class Derived extends Base {
+    public String foo(String s) { return s; }
+}
+
+public class WithVarargConstructor {
+    public WithVarargConstructor(int p, Object... objects) { }
+}
+
+public class T {
+    public Set<String> set;
+}