SPRING IN ACTION 第4版笔记-第四章ASPECT-ORIENTED SPRING-008-带参数的ADVICE

package soundsystem;

public interface CompactDisc {

  void play();
  void playTrack(int trackNumber);
}

 1 package soundsystem;
 2 
 3 import java.util.List;
 4 
 5 public class BlankDisc implements CompactDisc {
 6 
 7     private String title;
 8     private String artist;
 9     private List<String> tracks;
10 
11     public BlankDisc() {
12         super();
13     }
14 
15     public BlankDisc(String title, String artist, List<String> tracks) {
16         this.title = title;
17         this.artist = artist;
18         this.tracks = tracks;
19     }
20 
21     public void play() {
22         System.out.println("Playing " + title + " by " + artist);
23         for (String track : tracks) {
24             System.out.println("-Track: " + track);
25         }
26     }
27 
28     public String getTitle() {
29         return title;
30     }
31 
32     public void setTitle(String title) {
33         this.title = title;
34     }
35 
36     public String getArtist() {
37         return artist;
38     }
39 
40     public void setArtist(String artist) {
41         this.artist = artist;
42     }
43 
44     public List<String> getTracks() {
45         return tracks;
46     }
47 
48     public void setTracks(List<String> tracks) {
49         this.tracks = tracks;
50     }
51 
52     @Override
53     public void playTrack(int trackNumber) {
54         System.out.println("playTrack---->" + trackNumber);
55     }
56 
57 }

 1 package soundsystem;
 2 
 3 import java.util.HashMap;
 4 import java.util.Map;
 5 import org.aspectj.lang.annotation.Aspect;
 6 import org.aspectj.lang.annotation.Before;
 7 import org.aspectj.lang.annotation.Pointcut;
 8 
 9 @Aspect
10 public class TrackCounter {
11     private Map<Integer, Integer> trackCounts = new HashMap<Integer, Integer>();
12 
13     @Pointcut("execution(* soundsystem.CompactDisc.playTrack(int)) "
14             + "&& args(trackNumber)")
15     public void trackPlayed(int trackNumber) {
16     }
17 
18     @Before("trackPlayed(trackNumber)")
19     public void countTrack(int trackNumber) {
20         int currentCount = getPlayCount(trackNumber);
21         trackCounts.put(trackNumber, currentCount + 1);
22     }
23 
24     public int getPlayCount(int trackNumber) {
25         return trackCounts.containsKey(trackNumber) ? trackCounts
26                 .get(trackNumber) : 0;
27     }
28 }

 1 package soundsystem;
 2 
 3 import java.util.ArrayList;
 4 import java.util.List;
 5 
 6 import org.springframework.context.annotation.Bean;
 7 import org.springframework.context.annotation.Configuration;
 8 import org.springframework.context.annotation.EnableAspectJAutoProxy;
 9 
10 @Configuration
11 @EnableAspectJAutoProxy
12 public class TrackCounterConfig {
13     @Bean
14     public CompactDisc cd() {
15         BlankDisc cd = new BlankDisc();
16         cd.setTitle("Sgt. Pepper‘s Lonely Hearts Club Band");
17         cd.setArtist("The Beatles");
18         List<String> tracks = new ArrayList<String>();
19         tracks.add("Sgt. Pepper‘s Lonely Hearts Club Band");
20         tracks.add("With a Little Help from My Friends");
21         tracks.add("Lucy in the Sky with Diamonds");
22         tracks.add("Getting Better");
23         tracks.add("Fixing a Hole");
24         // ...other tracks omitted for brevity...
25         cd.setTracks(tracks);
26         return cd;
27     }
28 
29     @Bean
30     public TrackCounter trackCounter() {
31         return new TrackCounter();
32     }
33 }

 1 package soundsystem;
 2 
 3 import static org.junit.Assert.assertEquals;
 4 
 5 import org.junit.Rule;
 6 import org.junit.Test;
 7 import org.junit.contrib.java.lang.system.StandardOutputStreamLog;
 8 import org.junit.runner.RunWith;
 9 import org.springframework.beans.factory.annotation.Autowired;
10 import org.springframework.test.context.ContextConfiguration;
11 import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
12 
13 @RunWith(SpringJUnit4ClassRunner.class)
14 @ContextConfiguration(classes = TrackCounterConfig.class)
15 public class TrackCounterTest {
16     @Rule
17     public final StandardOutputStreamLog log = new StandardOutputStreamLog();
18     @Autowired
19     private CompactDisc cd;
20     @Autowired
21     private TrackCounter counter;
22 
23     @Test
24     public void testTrackCounter() {
25         cd.playTrack(1);
26         cd.playTrack(2);
27         cd.playTrack(3);
28         cd.playTrack(3);
29         cd.playTrack(3);
30         cd.playTrack(3);
31         cd.playTrack(7);
32         cd.playTrack(7);
33         assertEquals(1, counter.getPlayCount(1));
34         assertEquals(1, counter.getPlayCount(2));
35         assertEquals(4, counter.getPlayCount(3));
36         assertEquals(0, counter.getPlayCount(4));
37         assertEquals(0, counter.getPlayCount(5));
38         assertEquals(0, counter.getPlayCount(6));
39         assertEquals(2, counter.getPlayCount(7));
40     }
41 }