外语网络考试系统(6)

4.8数据库多表级联问题

多表级联举例；配置文件：

实体类

package cn.hxex.exam.model;

import java.util.Set; /**

* The POJO about role *

* @hibernate.class * table=\ *

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* @hibernate.query

* name=\

* query=\ *

* @struts.form

* name=\

* extends=\ *

* @author galaxy * */

public class Classes extends Base { /** * The Generated serial Version UID */ private static final long serialVersionUID = 3662683386669296609L; /** * @hibernate.property * column=\ */ private String title; /** * @hibernate.set * table=\ * lazy=\ * cascade=\ * @hibernate.key * column=\ * @hibernate.many-to-many * class=\ * column=\ */ private Set teachers; /** * @hibernate.set * inverse=\ * @hibernate.key * column=\ * @hibernate.one-to-many * class=\ */

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private Set students; /**

* Get the class name *

* @struts.form-field

* form-name=\ *

* @struts.validator * type=\ *

* @return Returns the title. */

public String getTitle() { return title; }

/**

* @param title The title to set. */

public void setTitle(String title) { this.title = title; }

/**

* @return Returns the teachers. */

public Set getTeachers() { return teachers; }

/**

* @param teachers The teachers to set. */

public void setTeachers(Set teachers) { this.teachers = teachers; }

/**

* @return Returns the students. */

public Set getStudents()

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{ return students; } /** * @param students The students to set. */ public void setStudents(Set students) { this.students = students; } }

package cn.hxex.exam.model; /**

* @hibernate.class table=\ *

* @hibernate.query name=\ *

* @struts.form name=\ *

* @author galaxy * */

public class Student extends User { /** * The Generated Serial Version UID */ private static final long serialVersionUID = -1970912575694406658L; /** * @hibernate.many-to-one column=\ * */ private Classes classes; /** * @return Returns the classes. */ public Classes getClasses() { return classes; }

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}

/**

* @param classes

* The classes to set. */

public void setClasses(Classes classes) { this.classes = classes; }

配置了many to one； 实体类中定义了Set。

本章主要描述了详细设计与系统实现的情况，具体分析了各模块的功能实现过程，并且详细的分析了实现各个功能模块的优缺点，最后叙述了系统实现的原理，以达到了整个系统初步形成。

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