1、模式定义

• 造者模式：将一个复杂对象的构建与它的表示分离，使得同样的构建过程可以创建不同的表示。建造者模式是一步一步创建一个复杂的对象，它允许用户只通过指定复杂对象的类型和内容就可以构建它们，用户不需要知道内部的具体构建细节。建造者模式属于对象创建型模式。根据中文翻译的不同，建造者模式又可以称为生成器模式。
• ==使用场景：在构建对象的过程可能要配置很多很多的参数，可以使用建造者模式。==

2、代码实现

public class Person {
    private String name;
    private int age;
    private double height;
    private double weight;

    private Person(Builder builder) {
        this.name=builder.name;
        this.age=builder.age;
        this.height=builder.height;
        this.weight=builder.weight;
    }

    public static class Builder{
        private String name;
        private int age;
        private double height;
        private double weight;
        public Builder name(String name){
            this.name=name;
            return this;
        }
        public Builder age(int age){
            this.age=age;
            return this;
        }
        public Builder height(double height){
            this.height=height;
            return this;
        }

        public Builder weight(double weight){
            this.weight=weight;
            return this;
        }

        public Person build(){
            return new Person(this);
        }
    }
}

public class TestDemo {
    public static void main(String[] args) {
        Person.Builder builder=new Person.Builder();
        Person person=builder.name("张三")
                              .age(18)
                              .height(178.5)
                              .weight(67.4)
                              .build();
    }
}

3、Android中Builder模式常见实例

• AlertDialog
• Okhttp
• Glide