builder模式

清疚 2023-10-07 11:23 7阅读 0赞

比较简单，看个例子：

package com.qs.mmeng.design.pattern.builder;
    
    import lombok.ToString;
    
    /**
     * tutorial
     *
     * @author qs
     * @date 2018/09/10
     */
    @ToString
    public class Student {
        
    
    	private Integer id;
    
    	private String no;
    
    	private String name;
    
    	private String sex;
    
    	private Integer age;
    
    	public Student() {
        
    
    	}
    
    	public Student(Student student) {
        
    		this.id = student.id;
    		this.no = student.no;
    		this.name = student.name;
    		this.sex = student.sex;
    		this.age = student.age;
    	}
    
    	public static Builder builder() {
        
    		return new Builder();
    	}
    
    	public static class Builder {
        
    
    		private Student target;
    
    		public Builder() {
        
    			this.target = new Student();
    		}
    
    		public Builder id(Integer id) {
        
    			target.id = id;
    			return this;
    		}
    
    		public Builder no(String no) {
        
    			target.no = no;
    			return this;
    		}
    
    		public Builder name(String name) {
        
    			target.name = name;
    			return this;
    		}
    
    		public Builder sex(String sex) {
        
    			target.sex = sex;
    			return this;
    		}
    
    		public Builder age(Integer age) {
        
    			target.age = age;
    			return this;
    		}
    
    		public Student build() {
        
    			return new Student(target);
    		}
    
    	}
    
    }

测试：

@Test
        public void builderTest() {
        
            Student student =
                    Student.builder().id(1).no(UUID.randomUUID().toString().replaceAll("-", ""))
                            .name("Tom").sex("男").age(12).build();
            System.out.println(student);
        }

输出：  
![在这里插入图片描述][watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE3NTg2ODIx_size_16_color_FFFFFF_t_70]

[watermark_type_ZmFuZ3poZW5naGVpdGk_shadow_10_text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE3NTg2ODIx_size_16_color_FFFFFF_t_70]: https://img-blog.csdnimg.cn/2020031922580494.png?x-oss-process=image/watermark,type_ZmFuZ3poZW5naGVpdGk,shadow_10,text_aHR0cHM6Ly9ibG9nLmNzZG4ubmV0L3FxXzE3NTg2ODIx,size_16,color_FFFFFF,t_70