Builder建造者模式

使用Builder内部内，set方法返回this.

public class MyBuilder {

    private String name;

    private String paswwd;

    public MyBuilder(Builder builder) {
        this.name = builder.name;
        this.paswwd = builder.paswwd;
    }

    public static class Builder {

        private String name;

        private String paswwd;

        public Builder setName(String name) {
            this.name = name;
            return this;
        }

        public Builder setPaswwd(String paswwd) {
            this.paswwd = paswwd;
            return this;
        }

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

}