标签：time open 分享图片 abstract action static bridge 分享 功能实现
桥梁模式的用意是"将抽象化(Abstraction)与实现化(Implementation)脱耦, 将"类的功能层次结构" 与 "类的实现层次结构"分离为两个独立的类层次结构.
public interface DisplayImpl {
void rawOpen();
void rawPrint();
void rawClose();
}
public class StringDisplayImpl implements DisplayImpl {
private String string;
private int width;
public StringDisplayImpl(String string) {
this.string = string;
this.width = string.getBytes().length;
}
public void rawOpen() {
printLine();
}
public void rawPrint() {
System.out.println("|" + string + "|");
}
public void rawClose() {
printLine();
}
private void printLine() {
System.out.print("+");
for (int i = 0; i < width; i++) {
System.out.print("-");
}
System.out.println("+");
}
}
在功能实现的最高层上关联了DisplayImpl接口, 在此处进行了桥接.
public class Display {
private DisplayImpl impl;
public Display(DisplayImpl impl) {
this.impl = impl;
}
public void open() {
impl.rawOpen();
}
public void print() {
impl.rawPrint();
}
public void close() {
impl.rawClose();
}
public final void display() {
open();
print();
close();
}
}
在Display类的基础上, 进行功能上的扩展. 扩展一个multiDisplay()功能.
public class CountDisplay extends Display {
public CountDisplay(DisplayImpl impl) {
super(impl);
}
public void multiDisplay(int times) {
open();
for (int i = 0; i < times; i++) {
print();
}
close();
}
}
用于测试运行
public class Main {
public static void main(String[] args) {
Display d1 = new Display(new StringDisplayImpl("Hello, China."));
Display d2 = new CountDisplay(new StringDisplayImpl("Hello, World."));
CountDisplay d3 = new CountDisplay(new StringDisplayImpl("Hello, Universe."));
d1.display();
d2.display();
d3.display();
d3.multiDisplay(5);
}
}
标签：time open 分享图片 abstract action static bridge 分享 功能实现
原文地址：https://www.cnblogs.com/noKing/p/9010888.html
