//==============================================================================
//      * Letsch Informatik *      www.LetsInfo.ch      CH-8636 Wald
//      Beratung, Ausbildung und Realisation in Software-Engineering
//==============================================================================
// Project   : Master of Advanced Studies in Software-Engineering / 2008
// Modul     : Java - Advanced Concepts
// Title     : Übung 2 / "Annotations und Reflection"
// Author    : Thomas Letsch
// Tab-Width : 2
/*///===========================================================================
* Description: Einsatz von Annotation und Reflection am Beispiel von Traceabilty.
* History    : 17.03.07: Initial Version. 
*            : 18.01.08: bin-Dir, Kosmetik.
*            : 21.01.08: filenames sortiert (es ist keine Ordnung spezifiziert 
*                        für File.list()).
* CVS        : $Revision: 1.6 $  $Date: 2008/01/24 13:51:17 $
/*///===========================================================================
//     1         2         3         4         5         6         7         8
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//==============================================================================


import static java.lang.System.out;

import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.io.File;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;


// Annotations: 

@Retention(RetentionPolicy.RUNTIME)
@interface Tracing {
  Ident   ident();
  Ident[] refs();
  String  contact() default "-";
}

@interface Ident {
  IdentType type();
  int       nr();
}

enum IdentType {UC, DE, IM}



// Test-Sceanario:

@Tracing(ident=@Ident(type=IdentType.DE, nr=1), 
         refs={@Ident(type=IdentType.UC, nr=1), @Ident(type=IdentType.UC, nr=2)})
class DesignClass1 {
}

@Tracing(ident=@Ident(type=IdentType.DE, nr=2), 
         refs={@Ident(type=IdentType.UC, nr=2)},
         contact="John Smith")
class DesignClass2 {
}

@Tracing(ident=@Ident(type=IdentType.DE, nr=3), 
         refs={@Ident(type=IdentType.UC, nr=1)})
class DesignClass3 {
}

@Tracing(ident=@Ident(type=IdentType.IM, nr=1), 
         refs={@Ident(type=IdentType.DE, nr=1)})
class ImplClass1 {
}

@Tracing(ident=@Ident(type=IdentType.IM, nr=2), 
         refs={@Ident(type=IdentType.DE, nr=1), @Ident(type=IdentType.DE, nr=2)})
class ImplClass2 {
}

@Tracing(ident=@Ident(type=IdentType.IM, nr=3), 
    refs={@Ident(type=IdentType.DE, nr=2)})
class ImplClass3 {
}

@Tracing(ident=@Ident(type=IdentType.IM, nr=9), 
    refs={@Ident(type=IdentType.IM, nr=3)},
    contact="Tom Miller")
class ImplClass9 {
}



class TracingTest {
  

  
  private static void printAnnotations(List<Class<?>> pTracingTypes) {
    for (Class<?> actualClass: pTracingTypes) {
      print("", actualClass);
    } 
  }
  
  

  private static void print(String pPrefix, Class<?> pActualClass) {
    out.print(pPrefix);
    out.printf("%-13s:  ", pActualClass.getName());
    Tracing t = pActualClass.getAnnotation(Tracing.class);
    out.printf("Ident: %s:%-4d:  ", t.ident().type(), t.ident().nr());
    String allIdentsStr = "";
    for (Ident ident: t.refs()) {
      allIdentsStr = allIdentsStr + getIdentString(ident)+",";
    }
    allIdentsStr = allIdentsStr.substring(0, allIdentsStr.length()-1);
    out.printf("Refs: %-12s:  ", allIdentsStr);
    out.println("Contact: " + t.contact());
  }
  
  
  
  private static String getIdentString(Ident pIdent) {
    return String.format("%s:%d", pIdent.type(), pIdent.nr());
  }
  
  
 
  private static void searchFor(List<Class<?>> pTracingTypes, IdentType pIT, 
                                int pNr, String pPrefix) {
    for (Class<?> actualClass: pTracingTypes) {
      Tracing t = (Tracing) actualClass.getAnnotation(Tracing.class);
      for (Ident id: t.refs()) {
        if ((id.type() == pIT) && (id.nr() == pNr)) {
          print(pPrefix, actualClass);
          searchFor(pTracingTypes, t.ident().type(), t.ident().nr(), pPrefix+"   ");
        }
      }
    }
  }
  
  
 
  public static void main(String[] pArgs) {
    if (pArgs.length == 0) {
      System.err.println("ERROR: no Argument !  (e.g. \"UC:2\")");
      System.exit(1);
    }
    File binDir = new File("bin");   // Class-Directory
    List<Class<?>> tracingTypes = new ArrayList<Class<?>>();
    out.print("\nTesting all Files in the bin-Directory: ");
    String[] filenames = binDir.list();
    Arrays.sort(filenames);
    for(String filename: filenames) {
      out.print("\nFile: "+filename);
      try {
        if ( ! filename.matches(".*\\.class$"))  // ".class" at End of Filename ?
          continue;   // this is not a Classfile
        filename = filename.substring(0, filename.lastIndexOf(".class"));
        out.print(" - loading...");
        Class<?> c = Class.forName(filename);
        Tracing t = (Tracing) c.getAnnotation(Tracing.class);
        if (t != null) {
          out.print(" found Tracing-Annotation!");
          tracingTypes.add(c);
        }
      } catch(ClassNotFoundException e){
        e.printStackTrace();
      }
    }
    
    out.println("\n\nPrinting all Tracing-Annotations:");
    printAnnotations(tracingTypes);
    
    out.println("\n\nSearching for: \""+pArgs[0]+"\"");
    String[] x = pArgs[0].split(":");
    String type = x[0];
    IdentType identType = IdentType.valueOf(type);
    int nr= Integer.valueOf(x[1]);
    searchFor(tracingTypes, identType, nr, "");
    
  } // End of main()
 
  

} // End of class TracingTest


/* Session-Log:
 
$ java -cp bin TracingTest UC:2

Testing all Files in the bin-Directory: 
File: DesignClass1.class - loading... found Tracing-Annotation!
File: DesignClass2.class - loading... found Tracing-Annotation!
File: DesignClass3.class - loading... found Tracing-Annotation!
File: Ident.class - loading...
File: IdentType.class - loading...
File: ImplClass1.class - loading... found Tracing-Annotation!
File: ImplClass2.class - loading... found Tracing-Annotation!
File: ImplClass3.class - loading... found Tracing-Annotation!
File: ImplClass9.class - loading... found Tracing-Annotation!
File: Tracing.class - loading...
File: TracingTest.class - loading...

Printing all Tracing-Annotations:
DesignClass1 :  Ident: DE:1   :  Refs: UC:1,UC:2   :  Contact: -
DesignClass2 :  Ident: DE:2   :  Refs: UC:2        :  Contact: John Smith
DesignClass3 :  Ident: DE:3   :  Refs: UC:1        :  Contact: -
ImplClass1   :  Ident: IM:1   :  Refs: DE:1        :  Contact: -
ImplClass2   :  Ident: IM:2   :  Refs: DE:1,DE:2   :  Contact: -
ImplClass3   :  Ident: IM:3   :  Refs: DE:2        :  Contact: -
ImplClass9   :  Ident: IM:9   :  Refs: IM:3        :  Contact: Tom Miller


Searching for: "UC:2"
DesignClass1 :  Ident: DE:1   :  Refs: UC:1,UC:2   :  Contact: -
   ImplClass1   :  Ident: IM:1   :  Refs: DE:1        :  Contact: -
   ImplClass2   :  Ident: IM:2   :  Refs: DE:1,DE:2   :  Contact: -
DesignClass2 :  Ident: DE:2   :  Refs: UC:2        :  Contact: John Smith
   ImplClass2   :  Ident: IM:2   :  Refs: DE:1,DE:2   :  Contact: -
   ImplClass3   :  Ident: IM:3   :  Refs: DE:2        :  Contact: -
      ImplClass9   :  Ident: IM:9   :  Refs: IM:3        :  Contact: Tom Miller

*/