Learn custom Java data type of Chapter XII of use

  1  / * 
  2  
  . 3  class as a parameter
   . 4  
  . 5  * / 
  . 6  
  . 7  public  class the Person {
   . 8  
  . 9     public  void Show () {
 10  
. 11       System.out.println ( "class as an argument" );
 12 is  
13 is     }
 14  
15  }
 16  
. 17  public  class the Test {
 18 is  
. 19      public  static  void main (String [] args) {
 20 is  
21 is          the Person P = new new the Person ();
 22 is  
23 is         Method (P);
 24  
25      }
 26 is  
27  // define a method, the class as an argument 
28  
29      public  static  void Method (the Person P) {
 30  
31 is            p.show ();
 32  
33 is      }
 34 is  
35  }
 36  
37 [  / * 
38 is  
39  type as the return value
 40  
41 is  * / 
42 is  
43 is  public  class Animal {
 44 is  
45      public  void RUN () {
 46 is  
47        System.out.println ( "type as the return value.");
 48 
 49    }
 50 
 51 }
 52 
 53 public class Test{
 54 
 55    public static void main(String[] args){
 56 
 57          Animal a = method();
 58 
 59          a.run();
 60 
 61    }
 62 
 63    public static Animal method(){
 64 
 65             Animal a = new Animal();
 66 
 67             return a;
 68 
 69     }
70  
71 is  }
 72  
73 is  / * 
74  
75    abstract class as a parameter
 76  
77  * / 
78  
79  public  abstract  class the Person {
 80  
81     public  abstract  void EAT ();
 82  
83  }
 84  
85  public  class Student the extends the Person {
 86  
87      public  void EAT () {
 88  
89           System.out.println ( "food" );
 90  
91 is      }
 92 
93  }
 94  
95  public  class the Test {
 96  
97      public  static  void main (String [] args) {
 98  
99             the Person P = new new Student ();
 100  
101             Method (P);
 102  
103       }
 104  
105      // define a method, the abstract class passed as arguments 
106  
107      public  static  void Method (the Person P) {
 108  
109            p.eat ();
 110  
111       }
 112  
113  }
 114 
115  / * 
1 16  
117  abstract class as the return value
 1 18  
119  * / 
120  
121  public  abstract  class Animal {
 122  
123      public  abstract  void RUN ();
 124  
125  }
 126  
127  public  class Dog {
 128  
129     public  void RUN () {
 130.  
131 is       the System .out.println ( "running" );
 132  
133      }
 134  
135  }
 136  
137  public  class the Test {
138  
139      public  static  void main (String [] args) {
 140  
141 is           Animal = A   Method ();
 142  
143          a.run ();
 144  
145     }
 146  
147    // define a method, as the return value to the abstract class 
148  
149     public  static Animal Method () {
 150  
151         Animal A = new new Dog ();
 152  
153         return A;
 154  
155     }
 156  
157  }
 158  
159  / * 
160.  
161 Interface as a parameter
 162  
163  * / 
164 is  
165  public  interface the Person {
 166  
167 is     public  abstract  void Work ();
 168  
169  }
 170.  
171 is  public  class Student the implements the Person {
 172  
173     public  void Work () {
 174  
175       System.out.println ( "work" );
 176  
177     }
 178  
179  }
 180 [  
181  public  class the Test {
 182  
183 is    public  static   void main (String [] args) {
 184  
185            the Person P = new new Student ();
 186  
187            Method (P);
 188  
189     }
 190  
191    // define a method, as a parameter to the interface 
192  
193     public  static  void Method (the Person P) {
 194  
195               p.work ();
 196  
197     }
 198  
199  }
 200 is  
201  / * 
202  
203  interfaces as the return value
 204  
205  * / 
206  
207 public interface Person{
208 
209     public abstract void work();
210 
211 }
212 
213 public class Teacher implements Person{
214 
215      public void work(){
216 
217        System.out.println("工作");
218 
219      }
220 
221 }
222 
223 public class Test{
224 
225    public static void main(String[] args){
226  
227          the Person P = Method ();
 228  
229          p.work ();
 230  
231     }
 232  
233     // define a method, as the return value to the interface 
234  
235     public  static the Person Method () {
 236  
237           the Person P = new new Teacher ( );
 238  
239           return P;
 240  
241     }
 242  
243 }