j2k: flatten test cases and testData directory structure

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

j2k/testData/fileOrElement/constructors/identifier.java

@@ -0,0 +1,33 @@
+public class Identifier {
+  private final String myName;
+  private boolean myHasDollar;
+  private boolean myNullable = true;
+
+  public Identifier(String name) {
+    myName = name;
+  }
+
+  public Identifier(String name, boolean isNullable) {
+    myName = name;
+    myNullable = isNullable;
+  }
+
+  public Identifier(String name, boolean hasDollar, boolean isNullable) {
+    myName = name;
+    myHasDollar = hasDollar;
+    myNullable = isNullable;
+  }
+
+  @Override
+  public String getName() {
+    return myName;
+  }
+}
+
+public class User {
+  public static void main() {
+     Identifier i1 = new Identifier("name", false, true);
+     Identifier i2 = new Identifier("name", false);
+     Identifier i3 = new Identifier("name");
+  }
+}