package com
import java.util.ArrayList
import java.util.List
public class Zhuq {
/*1 小红 123
2 小明 456
3 小强 123 */
public static void main(String[] args) {
List<Student>list = new ArrayList<>()
list.add(new Student("小红", "1", "123"))
list.add(new Student("小明", "2", "456"))
list.add(new Student("小强", "3", "123"))
for(Student bean :list){
if(list.contains(bean)){
System.out.println(bean)
}
}
}
}
package com
public class Student {
private String name
private String Id
private String pwe
public String getName() {
return name
}
public void setName(String name) {
this.name = name
}
public String getId() {
return Id
}
public void setId(String id) {
Id = id
}
public String getPwe() {
return pwe
}
public void setPwe(String pwe) {
this.pwe = pwe
}
@Override
public boolean equals(Object obj) {
if(obj instanceof Student){
if(((Student)obj).getPwe().equals( this.pwe) &&!((Student)obj).getId().equals( this.Id)){
return true
}
}
return false
}
@Override
public String toString() {
return "Student [name=" + name + ", Id=" + Id + ", pwe=" + pwe + "]"
}
public Student(String name, String id, String pwe) {
super()
this.name = name
Id = id
this.pwe = pwe
}
public Student() {
super()
}
}
获得某表所有列的信息：String sql = select * from tname//tname为某一表名
Connection conn = ....
Statement st = conn.createStatement()
ResultSet rs = st.rs = st.executeQuery(sql)
ResultSetMetaData rsmd = rs.getMetaData()
int colcount = rsmd.getColumnCount()//取得全部列数
for(int i=0i<colcounti++){
String colname = rsmd.getColumnName(i)//取得全部列名
}
以上为某表字段具体查询，如果是查询表的信息，如在mysql服务器上那样的查询结果的话,可以用一下代码:
ResultSet.executeQuery("show tables")可以的到所有的表信息。
ResultSet.executeQuery("describe tname")可以得到表的字段信息。//tname为表名
p.s :同样适用于jsp。
