ssh 实体关系分析确立（ER图

比較简单的方式就是依据模仿同类产品，依据同类产品的进行模仿，表单就是一个起码要加的字段，然后依据项目须要额外添加字段。

注意：实体类之间的引用关系还须要考虑性能的影响。如：单向或是双向。

表设计：

设计好后：

写实体类

建立实体类到数据库的关联关系

概述

5.实体关系分析

1.类结构:带箭头是单线关联,不带箭头是双向关联

----------------------------------------

class User
(1)<------(*) class Survey (1)-------(*) class Page (1)-------(*) class Question

{ { {
{

Integer id ;
Integer id ; Integer id ; Integer id ;

... ... ... ...


User user ; Survey survey ;    Page page ;


Set<Page> pages ;
Set<Question> questions ;


} } }
}

2.表结构

------------------------------------------------------------------

[users]

+----------+-------------+------+-----+---------+----------------+

| Field | Type | Null | Key | Default | Extra |

+----------+-------------+------+-----+---------+----------------+

| id | int(11) | NO | PRI | NULL | auto_increment |

| email | varchar(50) | YES | | NULL | |

| password | varchar(50) | YES | | NULL | |

| nickname | varchar(50) | YES | | NULL | |

| regdate | datetime | YES | | NULL | |

+----------+-------------+------+-----+---------+----------------+

[surveys]

+---------------+--------------+------+-----+---------+----------------+

| Field | Type | Null | Key | Default | Extra |

+---------------+--------------+------+-----+---------+----------------+

| id | int(11) | NO | PRI | NULL | auto_increment |

| title | varchar(200) | YES | | NULL | |

| pretext | varchar(50) | YES | | NULL | |

| nexttext | varchar(50) | YES | | NULL | |

| exittext | varchar(50) | YES | | NULL | |

| donetext | varchar(50) | YES | | NULL | |

| createtime | datetime | YES | | NULL | |

| userid | int(11) | YES | MUL | NULL | |

+---------------+--------------+------+-----+---------+----------------+

[pages]

+-------------+---------------+------+-----+---------+----------------+

| Field | Type | Null | Key | Default | Extra |

+-------------+---------------+------+-----+---------+----------------+

| id | int(11) | NO | PRI | NULL | auto_increment |

| title | varchar(200) | YES | | NULL | |

| description | varchar(200) | YES | | NULL | |

| surveyid | int(11) | YES | MUL | NULL | |

+-------------+---------------+------+-----+---------+----------------+

[questions]

+---------------------+--------------+------+-----+---------+----------------+

| Field | Type | Null | Key | Default | Extra |

+---------------------+--------------+------+-----+---------+----------------+

| id | int(11) | NO | PRI | NULL | auto_increment |

| questiontype | int(11) | YES | | NULL | |

| title | varchar(200) | YES | | NULL | |

| options | varchar(200) | YES | | NULL | |

| other | bit(1) | YES | | NULL | |

| otherstyle | int(11) | YES | | NULL | |

| otherselectoptions | varchar(200) | YES | | NULL | |

| matrixrowtitles | varchar(200) | YES | | NULL | |

| matrixcoltitles | varchar(200) | YES | | NULL | |

| matrixselectoptions | varchar(200) | YES | | NULL | |

| pageid | int(11) | YES | MUL | NULL | |

+---------------------+--------------+------+-----+---------+----------------+

3.映射文件

------------------------------------------

[User.hbm.xml]

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC

"-//Hibernate/Hibernate Mapping DTD 3.0//EN"

"http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

<class name="com.atguigu.surveypark.model.User" table="users">

<id name="id" column="id" type="integer">

<generator class="identity" />

</id>

<property name="email" column="email" type="string" length="50" />

<property name="password" column="password" type="string" length="50" />

<property name="nickName" column="nickname" type="string" length="50" />

<property name="regDate" column="regdate" type="timestamp" update="false"/>

</class>

</hibernate-mapping>

[Survey.hbm.xml]

<hibernate-mapping package="com.atguigu.surveypark.model">

<class name="Survey" table="surveys">

<id name="id" column="id" type="integer">

<generator class="identity" />

</id>

<property name="title" column="title" type="string" length="200" />

<property name="preText" column="pretext" type="string" length="50" />

<property name="nextText" column="nexttext" type="string" length="50" />

<property name="doneText" column="donetext" type="string" length="50" />

<property name="exitText" column="exittext" type="string" length="50" />

<property name="createTime" column="createtime" type="string" length="200" />



<many-to-one name="user" class="User" column="userid" />



<set name="pages" inverse="true">

<key column="surveyid" />

<one-to-many class="Page"/>

</set>

</class>

</hibernate-mapping>

[Page.hbm.xml]

<hibernate-mapping package="com.atguigu.surveypark.model">

<class name="Page" table="pages">

<id name="id" column="id" type="integer">

<generator class="identity" />

</id>

<property name="title" column="title" type="string" length="100" />

<property name="description" column="description" type="string" length="200" />



<many-to-one name="survey" class="Survey" column="surveyid" />



<set name="questions" inverse="true">

<key column="pageid" />

<one-to-many class="Question"/>

</set>

</class>

</hibernate-mapping>

[Question.hbm.xml]

<hibernate-mapping package="com.atguigu.surveypark.model">

<class name="Question" table="questions">

<id name="id" column="id" type="integer">

<generator class="identity" />

</id>

<property name="questionType" column="questiontype" type="integer" />

<property name="title" column="title" type="string" length="100" />

<property name="options" column="options" type="string" length="200" />

<property name="other" column="other" type="boolean"/>

<property name="otherStyle" column="otherstyle" type="integer" />

<property name="otherSelectOptions" column="otherselectoptions" type="string" length="200" />

<property name="matrixRowTitles" column="maxtrixrowtitles" type="string" length="200" />

<property name="matrixColTitles" column="matrixcoltitles" type="string" length="200" />

<property name="matrixSelectOptions" column="matrixselectoptions" type="string" length="200" />



<many-to-one name="page" class="Page" column="pageid" />

</class>

</hibernate-mapping>

具体代码例如以下：

Page.java

package com.atguigu.surveypark.model;

import java.util.HashSet;

import java.util.Set;

/**

 * 页面类

 */

public class Page {

	private Integer id;

	private String title = "未命名";

	private String description;

	//简历从Page到Survey之间多对一关联关系

	private Survey survey;

	//简历从Page到Question之间一对多关联关系

	private Set<Question> questions = new HashSet<>();

	public Integer getId() {

		return id;

	}

	public void setId(Integer id) {

		this.id = id;

	}

	public String getTitle() {

		return title;

	}

	public void setTitle(String title) {

		this.title = title;

	}

	public String getDescription() {

		return description;

	}

	public void setDescription(String description) {

		this.description = description;

	}

	public Survey getSurvey() {

		return survey;

	}

	public void setSurvey(Survey survey) {

		this.survey = survey;

	}

	public Set<Question> getQuestions() {

		return questions;

	}

	public void setQuestions(Set<Question> questions) {

		this.questions = questions;

	}

}

Page.hbm.xml:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC

    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.atguigu.surveypark.model">

	<class name="Page" table="pages">

		<id name="id" column="id" type="integer">

			<generator class="identity" />

		</id>

		<property name="title" column="title" type="string" length="100" />

		<property name="description" column="description" type="string" length="200" />

		<!-- 映射从Page到Survey之间多对一关联关系 -->

		<many-to-one name="survey" class="Survey" column="surveyid" />

		<!-- 映射从Page到Question之间一对多关联关系 -->

		<set name="questions" inverse="true">

			<key column="surveyid" />

			<one-to-many class="Question"/>

		</set>

	</class>

</hibernate-mapping>

Survey.java

package com.atguigu.surveypark.model;

import java.util.Date;

/**

 * 调查类

 */

public class Survey {

	private Integer id;

	private String title = "未命名";

	private String preText = "上一步";

	private String nextText = "下一步";

	private String exitText = "退出";

	private String doneText = "完毕";

	private Date createTime = new Date();

	//建立从Survey到User之间多对一关联关系

	private User user ;

	public User getUser() {

		return user;

	}

	public void setUser(User user) {

		this.user = user;

	}

	public Integer getId() {

		return id;

	}

	public void setId(Integer id) {

		this.id = id;

	}

	public String getTitle() {

		return title;

	}

	public void setTitle(String title) {

		this.title = title;

	}

	public String getPreText() {

		return preText;

	}

	public void setPreText(String preText) {

		this.preText = preText;

	}

	public String getNextText() {

		return nextText;

	}

	public void setNextText(String nextText) {

		this.nextText = nextText;

	}

	public String getExitText() {

		return exitText;

	}

	public void setExitText(String exitText) {

		this.exitText = exitText;

	}

	public String getDoneText() {

		return doneText;

	}

	public void setDoneText(String doneText) {

		this.doneText = doneText;

	}

	public Date getCreateTime() {

		return createTime;

	}

	public void setCreateTime(Date createTime) {

		this.createTime = createTime;

	}

}

Survey.hbm.xml:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC

    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.atguigu.surveypark.model">

	<class name="Survey" table="surveys">

		<id name="id" column="id" type="integer">

			<generator class="identity" />

		</id>

		<property name="title" column="title" type="string" length="200" />

		<property name="preText" column="pretext" type="string" length="50" />

		<property name="nextText" column="nexttext" type="string" length="50" />

		<property name="doneText" column="donetext" type="string" length="50" />

		<property name="exitText" column="exittext" type="string" length="50" />

		<property name="createTime" column="createtime" type="string" length="200" />		

		<!-- 映射从Survey到User之间多对一关联关系 -->

		<many-to-one name="user" class="User" column="userid" />

		<!-- 映射从Survey到Page之间一对多关联关系 -->

		<set name="pages" inverse="true">

			<key column="surveyid" />

			<one-to-many class="Page"/>

		</set>

	</class>

</hibernate-mapping>

Question.java:

package com.atguigu.surveypark.model;

/**

 * 问题类

 */

public class Question {

	//

	private Integer id;

	// 题型0-8

	private int questionType;

	//

	private String title;

	// 选项

	private String options;

	// 其它项

	private boolean other;

	// 其它项样式:0-无 1-文本框 2-下拉列表

	private int otherStyle;

	// 其它项下拉选项

	private String otherSelectOptions;

	// 矩阵式行标题集

	private String matrixRowTitles;

	// 矩阵式列标题集

	private String matrixColTitles;

	// 矩阵是下拉选项集

	private String matrixSelectOptions;

	//建立从Question到Page之间多对一关联关系

	private Page page;

	public Integer getId() {

		return id;

	}

	public void setId(Integer id) {

		this.id = id;

	}

	public int getQuestionType() {

		return questionType;

	}

	public void setQuestionType(int questionType) {

		this.questionType = questionType;

	}

	public String getTitle() {

		return title;

	}

	public void setTitle(String title) {

		this.title = title;

	}

	public String getOptions() {

		return options;

	}

	public void setOptions(String options) {

		this.options = options;

	}

	public boolean isOther() {

		return other;

	}

	public void setOther(boolean other) {

		this.other = other;

	}

	public int getOtherStyle() {

		return otherStyle;

	}

	public void setOtherStyle(int otherStyle) {

		this.otherStyle = otherStyle;

	}

	public String getOtherSelectOptions() {

		return otherSelectOptions;

	}

	public void setOtherSelectOptions(String otherSelectOptions) {

		this.otherSelectOptions = otherSelectOptions;

	}

	public String getMatrixRowTitles() {

		return matrixRowTitles;

	}

	public void setMatrixRowTitles(String matrixRowTitles) {

		this.matrixRowTitles = matrixRowTitles;

	}

	public String getMatrixColTitles() {

		return matrixColTitles;

	}

	public void setMatrixColTitles(String matrixColTitles) {

		this.matrixColTitles = matrixColTitles;

	}

	public String getMatrixSelectOptions() {

		return matrixSelectOptions;

	}

	public void setMatrixSelectOptions(String matrixSelectOptions) {

		this.matrixSelectOptions = matrixSelectOptions;

	}

	public Page getPage() {

		return page;

	}

	public void setPage(Page page) {

		this.page = page;

	}

}

Question.hbm.xml

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC

    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping package="com.atguigu.surveypark.model">

	<class name="Question" table="questions">

		<id name="id" column="id" type="integer">

			<generator class="identity" />

		</id>

		<property name="questionType" column="questiontype" type="integer" />

		<property name="title" column="title" type="string" length="100" />

		<property name="options" column="options" type="string" length="200" />

		<property name="other" column="other" type="boolean"/>

		<property name="otherStyle" column="otherstyle" type="integer" />

		<property name="otherSelectOptions" column="otherselectoptions" type="string" length="200" />

		<property name="matrixRowTitles" column="maxtrixrowtitles" type="string" length="200" />

		<property name="matrixColTitles" column="matrixcoltitles" type="string" length="200" />

		<property name="matrixSelectOptions" column="matrixselectoptions" type="string" length="200" />

		<!-- 映射从Question到Page之间多对一关联关系 -->

		<many-to-one name="page" class="Page" column="pageid" />

	</class>

</hibernate-mapping>

User.java

package com.atguigu.surveypark.model;

import java.util.Date;

/**

 * 用户类

 */

public class User {

	private Integer id;

	private String email;

	private String name;

	private String password;

	private String nickName;

	//注冊时间

	private Date regDate = new Date();

	public Integer getId() {

		return id;

	}

	public Date getRegDate() {

		return regDate;

	}

	public void setRegDate(Date regDate) {

		this.regDate = regDate;

	}

	public void setId(Integer id) {

		this.id = id;

	}

	public String getEmail() {

		return email;

	}

	public void setEmail(String email) {

		this.email = email;

	}

	public String getName() {

		return name;

	}

	public void setName(String name) {

		this.name = name;

	}

	public String getPassword() {

		return password;

	}

	public void setPassword(String password) {

		this.password = password;

	}

	public String getNickName() {

		return nickName;

	}

	public void setNickName(String nickName) {

		this.nickName = nickName;

	}

}

User.hbm.xml:

<?xml version="1.0"?>

<!DOCTYPE hibernate-mapping PUBLIC

    "-//Hibernate/Hibernate Mapping DTD 3.0//EN"

    "http://www.hibernate.org/dtd/hibernate-mapping-3.0.dtd">

<hibernate-mapping>

	<class name="com.atguigu.surveypark.model.User" table="users">

		<id name="id" column="id" type="integer">

			<generator class="identity" />

		</id>

		<property name="email" column="email" type="string" length="50" />

		<property name="password" column="password" type="string" length="50" />

		<property name="nickName" column="nickname" type="string" length="50" />

		<property name="regDate" column="regdate" type="timestamp"  update="false"/>

	</class>

</hibernate-mapping>

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ssh 实体关系分析确立（ER图－实体关系图）

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