Java implementation Strategy (strategy) mode

Policy mode: Behavioral mode

The same behavior, different processing algorithms are encapsulated separately. So they can replace each other.

1. Define a super-type interface and behavior method

2. Define different implementation classes and implement different algorithms for this behavior

/** * Strategy mode: For the same command (or behavior), different strategies to do different actions *  Product Promotion *  This class is: Cash Collection class *   *  @author Stone */public interface Icashsuper { Double Acceptcash (double money);}

/** * Normal cash charge * @author Stone * */public class Cashnormal implements Icashsuper {@Overridepublic double acceptcash (double m Oney) {return money;}}

/** * Discounted cash charge  * @author Stone * */public class Cashrebate implements Icashsuper {private double rebate;//Discount Public Cash Rebate (double rebate) {this.rebate = rebate;} @Overridepublic Double Acceptcash (double money) {return new BigDecimal (Money * rebate/10). Setscale (2, Bigdecimal.round_ HALF_UP). Doublevalue ();}}

/** * return  cash collected * @author stone * */public class Cashreturn implements Icashsuper {private double moneycondition;//Cashback Bottom amount private double returnmoney; Return amount public Cashreturn (double moneycondition, double returnmoney) {this.moneycondition = moneycondition; This.returnmoney = Returnmoney;} @Overridepublic Double Acceptcash (double money) {//Multiple rebate if (Money >= moneycondition) {return Money-math.floor (Money/ moneycondition) * Returnmoney;} else {return money;}}}

/** * Based on the policy class passed. Run the corresponding behavior * @author Stone * */public class Cashcontext {private Icashsuper casher;public Cashcontext () {}public Cashcontext ( Icashsuper casher) {this.casher = Casher;} public void Setcasher (Icashsuper casher) {this.casher = Casher;} According to the detailed policy object, the algorithm that invokes it behaves public double acceptcash (double money) {return This.casher.acceptCash (money);}}

/* * Policy (Strategy) mode of concern: the choice of behavior * Encapsulates a series of policy objects that the user chooses to use for the difference between a simple factory and a single one: * Policy mode. The incoming policy object is given to the context, which is called by the context wrapper policy object's method invocation, exposing the context's method interface * Simple Factory mode, passing in a simple argument. Create an object and then call the Factory object's method * different from the adornment mode: * Very obvious. Context does not need to implement (implements) the business interface, do not need to enhance the functionality of existing policy objects * Policy mode is used in algorithmic decision systems, such as Payroll */public class Test {public static void main (String [] args) {double money = 998;//original price Cashcontext Cashcontext = new Cashcontext (new Cashnormal ()); System.out.println ("Original price:" + cashcontext.acceptcash (money)); Usually the  strategy Cashcontext.setcasher (new Cashrebate (8.5)); System.out.println ("Hit 85 percent:" + cashcontext.acceptcash (money)); Discount   Strategy   85 percent Cashcontext.setcasher (new Cashreturn (300, 50)); SYSTEM.OUT.PRINTLN ("Full 300 Rebate:" + Cashcontext.acceptcash (money)); Rebate  policy    full 300 return 50}}

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Original Price: 998.0 dozen 85 Percent: 848.3 full 300 return 50:848

Java implementation Strategy (strategy) mode