Java8命令模式簡(jiǎn)化
public class Lignt {
//開燈操作
public void on(){
System.out.println("Open the Light");
}
//關(guān)燈操作
public void off(){
System.out.println("關(guān)燈操作");
}
}
public interface Command {
//執(zhí)行函數(shù)接口
public void execute();
}
//關(guān)燈指令
public class FilpDownCommand implements Command {
private Lignt lignt;
public FilpDownCommand(Lignt lignt) {
this.lignt = lignt;
}
public Lignt getLignt() {
return lignt;
}
public void setLignt(Lignt lignt) {
this.lignt = lignt;
}
@Override
public void execute() {
lignt.off();
}
}
//開燈指令
public class FillUpCommand implements Command {
private Lignt lignt;
public Lignt getLignt() {
return lignt;
}
public void setLignt(Lignt lignt) {
this.lignt = lignt;
}
public FillUpCommand(Lignt lignt) {
this.lignt = lignt;
}
@Override
public void execute() {
this.lignt.on();
}
}
//執(zhí)行者
public class LightSwitch {
//執(zhí)行順序
private List <Command>queue=new ArrayList <>( );
//添加執(zhí)行命令
public void add(Command command){
this.queue.add( command);
}
//執(zhí)行
public void execute(){
queue.forEach( e->{
//執(zhí)行命令操作
e.execute();
} );
}
}
public class LightCommandTest {
public static void main(String[] args) {
//實(shí)例化燈對(duì)象
Lignt light=new Lignt();
//開燈操作
Command fileUpcommand=new FillUpCommand( light);
//關(guān)燈指令
Command fileDownCommand=new FilpDownCommand( light );
//執(zhí)行者
LightSwitch lightSwitch=new LightSwitch();
lightSwitch.add( fileUpcommand );
lightSwitch.add( fileDownCommand );
lightSwitch.add( fileUpcommand );
lightSwitch.add( fileDownCommand );
lightSwitch.execute();
}
}
----------------------------------------------------Java8------------------------------------------------------
public class LightSwitchFP {
//首先我們直接使用Java8提供的Consumer函數(shù)接口作為我們的命令接口，因?yàn)橛辛薼ambda表達(dá)式削咆，
// 我們根本無(wú)需在單獨(dú)為具體命令對(duì)象創(chuàng)建類型恋博，而通過傳入labmda表達(dá)式來完成具體命令對(duì)象的創(chuàng)建雹仿；
private List <Consumer<Lignt>>queue=new ArrayList <>( );
public void add(Consumer<Lignt>consumer){
queue.add( consumer );
}
//執(zhí)行操作
public void execute(Lignt lignt){
queue.forEach( e->{
e.accept( lignt);
} );
}
}
public class LightJava8Command {
public static void main(String[] args) {
Lignt lignt=new Lignt();
//開燈
Consumer<Lignt>onLignt=lignt1 -> lignt.on();
//關(guān)燈
Consumer<Lignt>ofLignt=lignt1 -> lignt.off();
//創(chuàng)建執(zhí)行者
onLignt.andThen( ofLignt ).andThen( onLignt ).andThen( ofLignt ).accept( lignt );
// LightSwitchFP lightSwitch = new LightSwitchFP();
// lightSwitch.add(onLignt);
// lightSwitch.add(ofLignt);
// lightSwitch.add(onLignt);
// lightSwitch.add(ofLignt);
// lightSwitch.execute(lignt);
}
}
Consumer簡(jiǎn)介
Consumer的作用是給定義一個(gè)參數(shù),對(duì)其進(jìn)行(消費(fèi))處理,處理的方式可以是任意操作.
public interface Consumer<T> {
/**
* Performs this operation on the given argument.
*接收單個(gè)參數(shù)重付，返回為空
* @param t the input argument
*/
void accept(T t);
/**
這是一個(gè)用來做鏈?zhǔn)教幚淼姆椒ǎ摲椒ǚ祷氐氖且粋€(gè)Consumer對(duì)象障贸，假設(shè)調(diào)用者的Consumer對(duì)象為A错森，輸入?yún)?shù)Consumer對(duì)象設(shè)為B，那么返回的Consumer對(duì)象C的accept方法的執(zhí)行體就是A.accept()+B.accept()
*/
default Consumer<T> andThen(Consumer<? super T> after) {
Objects.requireNonNull(after);
return (T t) -> { accept(t); after.accept(t); };
}
}
demo如下
public class Java8_Example {
public static void main(String[] args) {
//Java8當(dāng)中的設(shè)計(jì)模式
//1.命令模式
Lignt lignts=new Lignt();
Consumer<Lignt>consumer=lignt -> System.out.println("TestManager");
Consumer<Lignt>consumer1=lignt -> System.out.println("TestManager1");
consumer.andThen( consumer1 ).accept( lignts );
}
}
控制臺(tái)輸出
TestManager
TestManager1
應(yīng)用場(chǎng)景可以為多個(gè)操作同時(shí)執(zhí)行
Process finished with exit code 0
策略模式
//策略模式
public interface Strategy {
//計(jì)算
public Integer compute(Integer a,Integer b);
}
//加
public class Add implements Strategy {
@Override
public Integer compute(Integer a, Integer b) {
return a+b;
}
}
//乘
public class Multiply implements Strategy {
@Override
public Integer compute(Integer a, Integer b) {
return a*b;
}
}
public class StrageGyTest {
public static void main(String[] args) {
Strategy strategy = new Add();
Context context = new Context( strategy );
Integer c = context.use( 1, 2 );
System.out.println( c );
}
}
----------------------------------------------Java8----------------------------------------------------------
public class ContextFp {
private BinaryOperator<Integer>binaryOperator;
public ContextFp(BinaryOperator binaryOperator){
this.binaryOperator=binaryOperator;
}
public Integer use(Integer first,Integer second){
Integer apply = binaryOperator.apply( first,second);
return apply;
}
}
枚舉封裝方法
public enum StrageEnum {
ADD( () -> (x, y) -> x + y ),
MULTIPLY( () -> (x, y) -> x * y );
//suppiler 作為java8的接口 返回一個(gè)對(duì)象的實(shí)例
//BinaryOperator 接受2個(gè)參數(shù)
private Supplier <BinaryOperator <Integer>> operation;
private StrageEnum(Supplier <BinaryOperator <Integer>> operation) {
this.operation = operation;
}
public BinaryOperator <Integer> get() {
return operation.get();
}
}
public class ContextFPEnum {
private StrageEnum strageEnum;
public ContextFPEnum(StrageEnum strageEnum){
this.strageEnum=strageEnum;
}
public Integer use(Integer first,Integer second){
return strageEnum.get().apply( first,second );
}
}
public class StrageGyJava8Test {
// public static final BinaryOperator <Integer> addBinary = (op1, op2) -> op1 + op2;
// public static final BinaryOperator <Integer> multiply = (op1, op2) -> op1 * op2;
public static void main(String[] args) {
// ContextFp contextFp=new ContextFp( addBinary );
// System.out.println(contextFp.use( 10,11));
// ContextFp contextFp1=new ContextFp( multiply );
// System.out.println(contextFp1.use( 1,2 ));
//累加
ContextFPEnum contextFPEnum = new ContextFPEnum( StrageEnum.ADD );
System.out.println( contextFPEnum.use( 1, 2 ) );
//乘
ContextFPEnum contextFPEnum1 = new ContextFPEnum( StrageEnum.MULTIPLY );
System.out.println( contextFPEnum1.use( 2, 3 ) );
}
}
