equals 方法重写的规则
判断一定相等(引用一致)
判断一定不等(类型不一致)
判断可能相等(需要把当前的对象给强转之后进行比较)
hashCode 重写规则
根据当前对象的唯一标识进行重写
如果为空就直接返回0,不为空就返回唯一标识的 hashCode 即可。
toString 重写规则,字符串加上 '' 区别非字符串
类名 + {field1=value1, field2=value2}
例如:Person{id=123,name="tom"}
例如:
package com.dada.shiro.entity; import java.io.Serializable; public class Organization implements Serializable { private Long id;//编号 private String name;// 组织机构名称 private Long parentId;// 父编号 private String parentIds;// 父编号列表 private Boolean available = Boolean.FALSE; public Long getId() { return id; } public void setId(Long id) { this.id = id; } public String getName() { return name; } public void setName(String name) { this.name = name; } public Long getParentId() { return parentId; } public void setParentId(Long parentId) { this.parentId = parentId; } public String getParentIds() { return parentIds; } public void setParentIds(String parentIds) { this.parentIds = parentIds; } public Boolean getAvailable() { return available; } public void setAvailable(Boolean available) { this.available = available; } public boolean isRootNode() { return parentId == 0; } public String makeSelfAsParentIds() { return getParentIds() + getId() + "/"; } @Override public boolean equals(Object that) { // 1.判断一定相等 if(this == that) return true; // 2.判断一定不等 if(that == null || getClass() != that.getClass()) return false; // 3.判断可能相等的情况 Organization thatObj = (Organization) that; if(id==null ? thatObj.id !=null : !id.equals(thatObj.id)) return false; return true; } @Override public int hashCode() { return id == null ? 0 : id.hashCode(); } @Override public String toString() { return "Organization {" + "id=" + id + ", name='" + name + "'" + ", parentId=" + parentId + ", parentIds='" + parentIds + "'" + ", available=" + available + "}"; } }