wamblee.org Git - utils/blob - system/general/src/main/java/org/wamblee/system/DefaultRequiredInterface.java

   1 package org.wamblee.system;
   2
   3 import java.util.Arrays;
   4
   5 public class DefaultRequiredInterface implements RequiredInterface {
   6
   7         private String _name;
   8         private Class[] _required;
   9         private ProvidedInterface _provider;
  10
  11         public DefaultRequiredInterface(String aName, Class aInterface) {
  12                 this(aName, new Class[] { aInterface });
  13         }
  14
  15         public DefaultRequiredInterface(String aName, Class[] aInterfaces) {
  16                 _name = aName;
  17                 _required = aInterfaces;
  18         }
  19
  20         @Override
  21         public String getName() {
  22                 return _name;
  23         }
  24
  25         @Override
  26         public boolean implementedBy(ProvidedInterface aDescriptor) {
  27                 Class[] provided = aDescriptor.getInterfaceTypes();
  28                 for (Class required : _required) {
  29                         if ( !serviceProvided(required, provided)) {
  30                                 return false;
  31                         }
  32                 }
  33                 // all required interfaces are provided.
  34                 return true;
  35         }
  36
  37         /**
  38          * Check if the required interface is implemented by one of the provided interfaces.
  39          * @param aRequired required interface
  40          * @param aProvided Provided interfaces.
  41          * @return
  42          */
  43         private boolean serviceProvided(Class aRequired, Class[] aProvided) {
  44                 for (Class provided: aProvided) {
  45                         try {
  46                                 provided.asSubclass(aRequired);
  47                                 return true;
  48                         } catch (ClassCastException e) {
  49                                 // No match, try the next one.
  50                         }
  51                 }
  52                 return false;
  53         }
  54
  55         @Override
  56         public ProvidedInterface getProvider() {
  57                 return _provider;
  58         }
  59
  60         @Override
  61         public void setProvider(ProvidedInterface aProvider) {
  62                 _provider = aProvider;
  63         }
  64
  65         @Override
  66         public <T> T getImplementation(Class<T> aClass) {
  67                 if ( _provider == null ) {
  68                         return null;
  69                 }
  70                 return (T)_provider.getImplementation();
  71         }
  72
  73         @Override
  74         public boolean equals(Object obj) {
  75                 if ( !(obj instanceof DefaultRequiredInterface)) {
  76                         return false;
  77                 }
  78                 DefaultRequiredInterface descr = (DefaultRequiredInterface)obj;
  79                 if ( _required.length != descr._required.length ) {
  80                         return false;
  81                 }
  82                 String[] interfaces1 = new String[_required.length];
  83                 String[] interfaces2 = new String[_required.length];
  84                 for (int i = 0; i < _required.length; i++) {
  85                         interfaces1[i] = _required[i].getName();
  86                         interfaces2[i] = descr._required[i].getName();
  87                 }
  88                 Arrays.sort(interfaces1);
  89                 Arrays.sort(interfaces2);
  90                 return Arrays.equals(interfaces1, interfaces2);
  91         }
  92
  93         @Override
  94         public int hashCode() {
  95                 return _required.hashCode();
  96         }
  97
  98         @Override
  99         public String toString() {
 100                 StringBuffer buf = new StringBuffer();
 101                 for (Class intf: _required) {
 102                         buf.append("." + intf.getName());
 103                 }
 104                 return buf.toString();
 105         }
 106 }