设计模式

建造者模式

将一个复杂对象的构建和它的表示分离,使得同样的构建过程可以创建不同的表示.
用户只需指定需要构建的类型,过程和细节不需知道.

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package builder;

/**
 * Created by hero on 17-2-18.
 */
public interface Builder {
    /** 不可缺少的步骤 */
    void hands();
    void legs();
}

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package builder;

/**
 * Created by hero on 17-2-18.
 */
public class FatBuilder implements Builder{
    public void hands() {
        System.out.println("胖手");
    }

    public void legs() {
        System.out.println("胖腿");
    }
}

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package builder;

/**
 * Created by hero on 17-2-18.
 */
public class ThinBuilder implements Builder {
    public void hands() {
        System.out.println("瘦手");
    }

    public void legs() {
        System.out.println("瘦腿");
    }
}

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package builder;

/**
 * Created by hero on 17-2-18.
 */
public class Director {
    private Builder builder;

    public Director(Builder builder) {
        this.builder = builder;
    }

    /** 封装具体过程 */
    public void build() {
        builder.hands();
        builder.legs();
    }

    public void setBuilder(Builder builder) {
        this.builder = builder;
    }
}

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package builder;

/**
 * Created by hero on 17-2-18.
 */
public class Main {
    public static void main(String[] args) {
        Director director = new Director(new FatBuilder());
        director.build();

        director.setBuilder(new ThinBuilder());
        director.build();
    }
}