設計模式學習—組合實體模式(Composite Entity Design Pattern)
阿新 • • 發佈：2019-02-17
一、我的理解
該模式是EJB開發時用到的一種模式。目前我的理解是該模式的作用是將各個細粒度的業務單獨分割出來，然後由一個粗粒度的類來管理這些實體類。二、實現方式
每個業務對應一個實體類，然後由一個粗粒度的類來生成和管理這些類三、例項
Java例項
DependencyObject1類：實體類一
DependencyObject2類：實體類二package com.study.dp.compositeentity; public class DependencyObject1 { private String data; public String getData() { return data; } public void setData(String data) { this.data = data; } }
package com.study.dp.compositeentity;
public class DependencyObject2 {
private String data;
public String getData() {
return data;
}
public void setData(String data) {
this.data = data;
}
}
CompositeEntity類：組合實體類，通過呼叫粗粒度物件來管理實體package com.study.dp.compositeentity; public class CoarseGrainedObject { DependencyObject1 do1 = new DependencyObject1(); DependencyObject2 do2 = new DependencyObject2(); public void setData(String data1, String data2) { do1.setData(data1); do2.setData(data2); } public String[] getData() { return new String[] {do1.getData(), do2.getData()}; } }
Client類：客戶端類package com.study.dp.compositeentity; public class CompositeEntity { private CoarseGrainedObject cgo = new CoarseGrainedObject(); public void setData(String data1, String data2) { cgo.setData(data1, data2); } public String[] getData() { return cgo.getData(); } }
package com.study.dp.compositeentity;
public class Client {
private CompositeEntity compositeEntity = new CompositeEntity();
public void printData() {
for(int i=0; i<compositeEntity.getData().length; i++) {
System.out.println("Data: "+compositeEntity.getData()[i]);
}
}
public void setData(String data1, String data2) {
compositeEntity.setData(data1, data2);
}
}
package com.study.dp.compositeentity;
public class Demo {
public static void main(String[] args) {
Client client = new Client();
client.setData("Test", "Data");
client.printData();
client.setData("Second Test", "Data1");
client.printData();
}
}