studentservice.java

高校学生信息管理,实现了高校信息化

//service层,调用数据库操作的方法

package student;

import java.sql.SQLException;
import java.util.ArrayList;

public class StudentService 
{
	private static final long serialVersionUID = -127912198931100551L;

	StudentDao studentdao=new StudentDao();
	
	//添加学生信息
	public boolean addStudent(Student student)
	{
		boolean flag = false;
		try 
		{
			flag = this.isInsert(student);
			if (flag)
			{
				studentdao.add(student);
			}

		}
		catch (SQLException e) 
		{
			flag = false;
			e.printStackTrace();
		}
		
		return flag;
	}
	
	//检查主键是否冲突
	public boolean isInsert(Student student) 
	{
		boolean flag = false;
		try 
		{
			flag = studentdao.canInsert(student.getStudentNum());
		} 
		catch (SQLException e)
		{
			System.out.println(e.getMessage());
		}
		return flag;
	}
	
    //	删除学生信息
	public void del(Student st) throws SQLException
	{
		studentdao.delete(st);
	}
	public void del(String str) throws Exception
	{
		studentdao.deleteStudent(str);
	}
	
    //	查询学生信息
	public ArrayList<Student> find(String str1,String str2,String str3,String str4) throws SQLException
	{
		ArrayList<Student> studentlist=new ArrayList<Student>();
		if(!str3.isEmpty())
		{
			String sql =String.format("select * from student where num='%s'",str3);
			studentlist=studentdao.getStudentList(sql);
		}
		else
		{
			String sql;
			sql="select * from student where";
			String strAdd; 

			if(!str1.isEmpty()) 
			{
				strAdd=String.format(" name='%s'", str1);
				sql += strAdd;
			}
			if(!str2.isEmpty()) 
			{
				if(!str1.isEmpty())
					strAdd=String.format(" AND age='%s'", str2);
				else strAdd=String.format(" age='%s'", str2);
				sql += strAdd;
			}
			if(!str4.isEmpty()) 
			{
				if(!str1.isEmpty()||!str2.isEmpty())
					strAdd=String.format(" AND class='%s'", str4);
				else strAdd=String.format(" class='%s'", str4);
				sql += strAdd;
			}
			studentlist=studentdao.getStudentList(sql);
		}
		return studentlist;
	}
	
    //	修改学生信息
	public boolean mod(Student student,String numid) throws SQLException//modify(ArrayList<Student> studentlist,HttpServletRequest request,HttpServletResponse response) throws IOException
	{
		boolean flag=false;
		Student oldst=new Student();
		oldst=studentdao.returnstudent(numid);
		flag=studentdao.modify(oldst, student, numid);		
		return flag;
	}
	
	

}