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herman_liu76:
我们的action中不写逻辑,只处理http有关的数据准备与返 ...
有没有人在struts2的action这一层做事务控制? -
xiaoxin5230:
呵呵,沙市小吃我觉得是最好吃的,物美价廉
沙市美食-过早篇 -
Durian:
面向数据库设计不能使用oo的全部特性。
ER Studio从设计模型生成JPA Entity -
xiaofengtoo:
我比较喜欢楼主的想法。对于老板与客户不关注那么多,能快速开发, ...
ER Studio从设计模型生成JPA Entity -
魔力猫咪:
ER的模型是数据库模型不是对象模型。
ER Studio从设计模型生成JPA Entity
主要是参考ER Studio设计模型 代码生成 。脚本如下:
ER Studio的模型难道就不是对象?难道必须写成JAVA Class才是对象?
'利用ER/Studio的Macro生成JPA Entity '目前对于多对多关联和复合主键的支持还没有完成 'By Colin 2009/3/24 Sub Main() Dim fso As Object Dim entNames As Variant Dim entCount As Variant Dim entLoop As Integer 'ER/Studio variables Dim mdl As Model Dim subMdl As SubModel Dim ent As Entity Dim classPath As Variant classPath = "d:\entity\" Set mdl = DiagramManager.ActiveDiagram.ActiveModel Set subMdl = mdl.ActiveSubModel 'get the entities list & count subMdl.EntityNames(entNames, entCount) 'sort the entities by name(alphabetic sort) Call dhQuickSort(entNames) For entLoop = 0 To entCount - 1 Set ent = mdl.Entities.Item(entNames(entLoop)) Set fso = CreateObject("Scripting.FileSystemObject") 'DAO class file Set csFile = fso.CreateTextFile(classPath & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & ".java", True) Call WriteEntity(csFile, ent, subMdl.Name) csFile.Close Next End Sub Sub WriteEntity(csFile As Object,ent As Entity, subModelName As String) Dim content As String 'DAO class Call Write2File(csFile, NamespaceStart(ent.EntityName, subModelName)) content = content & vbTab & "/// <summary>" & vbCrLf content = content & vbTab & "/// Data Access Object for " & ent.EntityName & vbCrLf content = content & vbTab & "/// </summary>" & vbCrLf content = content & vbTab & "@Entity" & vbCrLf content = content & vbTab & "@Table(name = """ & ent.TableName & """, catalog = ""wcs_db"", uniqueConstraints = {})" & vbCrLf content = content & vbTab & "public class " & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & " extends BaseEntity" & vbCrLf content = content & vbTab & "{" & vbCrLf content = content & EntityPrivateDeclare(ent) & vbCrLf content = content & vbTab & vbTab & "/// <summary>" & vbCrLf content = content & vbTab & vbTab & "/// default constructor for " & ent.EntityName & vbCrLf content = content & vbTab & vbTab & "/// </summary>" & vbCrLf content = content & vbTab & vbTab & "public " & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & "()" & vbCrLf content = content & vbTab & vbTab & "{" & vbCrLf content = content & vbTab & vbTab & "}" & vbCrLf & vbCrLf content = content & EntityPublicDeclare(ent) content = content & EntityOverrideMethod(ent) content = content & vbTab & "}" Call Write2File(csFile, content) End Sub Function DataType2ClassType(attr As AttributeObj) 'return the .net data type corresponding to the sql type Dim classType As String Select Case attr.Datatype Case "CHAR" classType = "String" Case "VARCHAR2" classType = "String" Case "NVARCHAR" classType = "String" Case "NVARCHAR2" classType = "String" Case "VARCHAR" classType = "String" Case "NTEXT" classType = "String" Case "DATETIME" classType = "Date" Case "DATE" classType = "Date" Case "DECIMAL" classType = "java.math.BigDecimal" Case "FLOAT" classType = "Float" Case "NUMERIC" If attr.DataScale = 0 Then If attr.DataLength > 9 Then classType = "java.math.BigDecimal" Else classType = "Integer" End If Else If attr.DataScale < 29 Then classType = "java.math.BigDecimal" Else classType = "Double" End If End If Case "INTEGER" classType = "Integer" Case "BIGINT" classType = "Long" Case "BIT" classType = "Boolean" Case Else classType = "String" End Select DataType2ClassType = classType End Function Function AttributePrivateName(entName As String) Dim length As Integer Dim result As String length = Len(entName) If length >0 Then result = StrConv(Left$(entName,1),vbLowerCase) & Right$(entName,length-1) End If AttributePrivateName = result End Function Function AttributeName(entName As String) Dim result As String Dim t As Integer Dim tempStr As String Dim length As Integer length = Len(entName) entName = StrConv(Left$(entName,1),vbUpperCase) & Right$(entName,length-1) t=InStr(1,entName,"_") If t > 0 Then tempStr = Right$(entName,length - t) length = Len(tempStr) tempStr = StrConv(Left$(tempStr,1),vbUpperCase) & Right$(tempStr,length-1) result = result & Left$(entName,t-1) & tempStr Else result = entName End If Do While t>0 length = Len(result) t=InStr(1,result,"_") tempStr = Right$(result,length-t) length = Len(tempStr) tempStr = StrConv(Left$(tempStr,1),vbUpperCase) & Right$(tempStr,length-1) If t>0 Then result = Left$(result,t-1) & tempStr End If Loop AttributeName = result End Function Function EntityPrivateDeclare(ent As Entity) Dim result As String Dim attr As AttributeObj Dim Index As Integer Dim parent As Entity Dim child As Entity Dim rl As Relationship Dim prl As Relationship For Index=1 To ent.Attributes.Count Set attr=FindAttribute(ent.Attributes, Index) If Not attr Is Nothing Then If attr.PrimaryKey Then result=result & vbTab & vbTab & "private " & DataType2ClassType(attr) & " id;" & vbCrLf Else If attr.ForeignKey Then 'Set parent = attr.GetParent() 'result=result & vbTab & vbTab & "private " & AttributeName(StrConv((parent.EntityName),vbLowerCase)) & " " & AttributePrivateName(AttributeName(StrConv((parent.EntityName),vbLowerCase))) & ";" & vbCrLf Else result=result & vbTab & vbTab & "private " & DataType2ClassType(attr) & " " & AttributePrivateName(AttributeName(StrConv(attr.AttributeName,vbLowerCase))) & ";" & vbCrLf End If End If End If Next For Each rl In ent.ChildRelationships Set parent = rl.ParentEntity result=result & vbTab & vbTab & "private " & AttributeName(StrConv((parent.EntityName),vbLowerCase)) & " " & AttributePrivateName(AttributeName(StrConv((parent.EntityName),vbLowerCase))) & ";" & vbCrLf Next For Each prl In ent.ParentRelationships Set child = prl.ChildEntity result=result & vbTab & vbTab & "private Set<" & AttributeName(StrConv((child.EntityName),vbLowerCase)) & "> " & AttributePrivateName(AttributeName(StrConv((child.EntityName),vbLowerCase))) & "s = new HashSet<" & AttributeName(StrConv((child.EntityName),vbLowerCase)) & ">();" & vbCrLf Next EntityPrivateDeclare=result End Function Function EntityPublicDeclare(ent As Entity) Dim result As String Dim attr As AttributeObj Dim Index As Integer Dim parent As Entity Dim rl As Relationship Dim fk As FKColumnPair Dim keyID As String Dim child As Entity Dim prl As Relationship For Index=1 To ent.Attributes.Count Set attr = FindAttribute(ent.Attributes, Index) If Not attr Is Nothing Then 'result = result & vbTab & vbTab & "private " & DataType2ClassType(attr) & " " & attr.AttributeName & ";" & vbCrLf If attr.PrimaryKey Then result = result & vbTab & vbTab & "/// <summary>" & vbCrLf result = result & vbTab & vbTab & "/// " & attr.AttributeName & vbCrLf result = result & vbTab & vbTab & "/// </summary>" & vbCrLf result = result & AnnotationColumn(attr) result = result & vbTab & vbTab & "@Override" & vbCrLf result = result & vbTab & vbTab & "public " & DataType2ClassType(attr) & " getId(){" & vbCrLf result = result & vbTab & vbTab & vbTab & "return this.id;" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf result = result & vbTab & vbTab & "@Override" & vbCrLf result = result & vbTab & vbTab & "public void setId(" & DataType2ClassType(attr) & " id){" & vbCrLf result = result & vbTab & vbTab & vbTab & "this.id = id;" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf Else If attr.ForeignKey Then Else result = result & vbTab & vbTab & "/// <summary>" & vbCrLf result = result & vbTab & vbTab & "/// " & attr.AttributeName & vbCrLf result = result & vbTab & vbTab & "/// </summary>" & vbCrLf result = result & AnnotationColumn(attr) result = result & vbTab & vbTab & "public " & DataType2ClassType(attr) & " " & atrributeGetMethod(attr.ColumnName) & "(){" & vbCrLf result = result & vbTab & vbTab & vbTab & "return this." & AttributePrivateName(AttributeName(StrConv(attr.AttributeName,vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf result = result & vbTab & vbTab & "public void " & atrributeSetMethod(attr.ColumnName) & "(" & DataType2ClassType(attr) & " " & AttributePrivateName(AttributeName(StrConv(attr.AttributeName,vbLowerCase))) & "){" & vbCrLf result = result & vbTab & vbTab & vbTab & "this." & AttributePrivateName(AttributeName(StrConv(attr.AttributeName,vbLowerCase))) & " = " & AttributePrivateName(AttributeName(StrConv(attr.AttributeName,vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf End If End If End If Next For Each rl In ent.ChildRelationships Set parent = rl.ParentEntity If Not parent Is Nothing Then 'result = result & vbTab & vbTab & "/// <summary>" & vbCrLf 'result = result & vbTab & vbTab & "/// " & attr.AttributeName & vbCrLf 'result = result & vbTab & vbTab & "/// </summary>" & vbCrLf 'result = result & AnnotationColumn(attr) For Each fk In rl.FKColumnPairs keyID = fk.ParentAttribute.AttributeName Next result = result & AnnotationFK(parent,keyID) 'result=result & vbTab & vbTab & "private " & AttributeName(StrConv((parent.EntityName),vbLowerCase)) & " " & AttributePrivateName(AttributeName(StrConv((parent.EntityName),vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "public " & AttributeName(StrConv(parent.EntityName,vbLowerCase)) & " " & atrributeGetMethod(parent.EntityName) & "(){" & vbCrLf result = result & vbTab & vbTab & vbTab & "return this." & AttributePrivateName(AttributeName(StrConv((parent.EntityName),vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf result = result & vbTab & vbTab & "public void " & atrributeSetMethod(parent.EntityName) & "(" & AttributeName(StrConv((parent.EntityName),vbLowerCase)) & " " & AttributePrivateName(AttributeName(StrConv(parent.EntityName,vbLowerCase))) & "){" & vbCrLf result = result & vbTab & vbTab & vbTab & "this." & AttributePrivateName(AttributeName(StrConv(parent.EntityName,vbLowerCase))) & " = " & AttributePrivateName(AttributeName(StrConv(parent.EntityName,vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf End If Next For Each prl In ent.ParentRelationships Set child = prl.ChildEntity If Not child Is Nothing Then result = result & AnnotationChild(ent) result = result & vbTab & vbTab & "public Set<" & AttributeName(StrConv(child.EntityName,vbLowerCase)) & "> " & atrributeGetMethod(child.EntityName) & "s(){" & vbCrLf result = result & vbTab & vbTab & vbTab & "return this." & AttributePrivateName(AttributeName(StrConv((child.EntityName & "s"),vbLowerCase))) & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf result = result & vbTab & vbTab & "public void " & atrributeSetMethod(child.EntityName & "s") & "(Set<" & AttributeName(StrConv((child.EntityName),vbLowerCase)) & "> " & AttributePrivateName(AttributeName(StrConv(child.EntityName,vbLowerCase))) & "s){" & vbCrLf result = result & vbTab & vbTab & vbTab & "this." & AttributePrivateName(AttributeName(StrConv(child.EntityName,vbLowerCase))) & "s = " & AttributePrivateName(AttributeName(StrConv(child.EntityName,vbLowerCase))) & "s;" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbCrLf End If Next EntityPublicDeclare=result End Function Function atrributeGetMethod(attr As String) atrributeGetMethod = "get" & AttributeName(StrConv(attr,vbLowerCase)) End Function Function atrributeSetMethod(attr As String) atrributeSetMethod = "set" & AttributeName(StrConv(attr,vbLowerCase)) End Function Function AppendToString(attr As AttributeObj, Val As String) Dim result As String result=Val If Len(Val)>0 Then result = result & "id.toString()" Else result = "id.toString()" End If AppendToString=result End Function Function AppendGetHashCode(attr As AttributeObj, Val As String) Dim result As String result=Val If Len(Val)>0 Then result = result & " + " & "id.hashCode()" Else result ="id.hashCode()" End If AppendGetHashCode=result End Function Function AppendEquals(ent As Entity, attr As AttributeObj, Val As String) Dim result As String result=Val If Len(Val)>0 Then result = result & "&& (id) & == (obj instanceof " & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & ")." & AttributeName(StrConv(attr.AttributeName,vbLowerCase)) & ")" Else result = "( id == ((" & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & ")obj).getId() )" End If AppendEquals=result End Function Function EntityOverrideMethod(ent As Entity) Dim result As String, toString As String, hashCode As String, equals As String Dim attr As AttributeObj Dim existsPrimary As Boolean For Each attr In ent.Attributes If attr.PrimaryKey Then toString = AppendToString(attr, toString) hashCode = AppendGetHashCode(attr, hashCode) equals = AppendEquals(ent, attr, equals) existsPrimary=True End If Next If existsPrimary Then result = result & vbTab & vbTab & "/// <summary>" & vbCrLf result = result & vbTab & vbTab & "///" & vbCrLf result = result & vbTab & vbTab & "/// </summary>" & vbCrLf result = result & vbTab & vbTab & "/// <returns></returns>" & vbCrLf result = result & vbTab & vbTab & "@Override" & vbCrLf result = result & vbTab & vbTab & "public String toString()" & vbCrLf result = result & vbTab & vbTab & "{" & vbCrLf result = result & vbTab & vbTab & vbTab & "return " & toString & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & "/// <summary>" & vbCrLf result = result & vbTab & vbTab & "///" & vbCrLf result = result & vbTab & vbTab & "/// </summary>" & vbCrLf result = result & vbTab & vbTab & "/// <returns></returns>" & vbCrLf result = result & vbTab & vbTab & "@Override" & vbCrLf result = result & vbTab & vbTab & "public int hashCode()" & vbCrLf result = result & vbTab & vbTab & "{" & vbCrLf result = result & vbTab & vbTab & vbTab & "return " & hashCode & ";" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & "/// <summary>" & vbCrLf result = result & vbTab & vbTab & "///" & vbCrLf result = result & vbTab & vbTab & "/// </summary>" & vbCrLf result = result & vbTab & vbTab & "/// <returns></returns>" & vbCrLf result = result & vbTab & vbTab & "@Override" & vbCrLf result = result & vbTab & vbTab & "public boolean equals(Object obj)" & vbCrLf result = result & vbTab & vbTab & "{" & vbCrLf result = result & vbTab & vbTab & vbTab & "boolean result = false;" & vbCrLf result = result & vbTab & vbTab & vbTab & "if (obj instanceof " & AttributeName(StrConv(ent.EntityName,vbLowerCase)) & ")" & vbCrLf result = result & vbTab & vbTab & vbTab & "{" & vbCrLf result = result & vbTab & vbTab & vbTab & vbTab & "result = " & equals & ";" & vbCrLf result = result & vbTab & vbTab & vbTab & "}" & vbCrLf result = result & vbTab & vbTab & vbTab & "return result;" & vbCrLf result = result & vbTab & vbTab & "}" & vbCrLf End If EntityOverrideMethod=result End Function Function AnnotationColumn(attr As AttributeObj) Dim result As String If Not attr Is Nothing Then If attr.PrimaryKey Then result = vbTab & vbTab & "@Id" & vbCrLf result = result & vbTab & vbTab & "@GeneratedValue(strategy = GenerationType.AUTO)" & vbCrLf End If If attr.ForeignKey Then result = vbTab & vbTab & "@ManyToOne(cascade = {CascadeType.PERSIST,CascadeType.MERGE})" &vbCrLf result = result & vbTab & vbTab & "@JoinColumn(name=""" & attr.ColumnName & """)" & vbCrLf Else result = vbTab & vbTab & "@Column(name = """ & attr.ColumnName & """, unique = false, nullable = " If attr.NullOption = "NULL" Then result = result & "false" Else result = result & "true" End If result = result & ", insertable = true, updatable = true, length = " & attr.DataLength & ")" &vbCrLf End If End If AnnotationColumn = result End Function Function AnnotationFK(parent As Entity,keyID As String) Dim result As String If Not parent Is Nothing Then result = vbTab & vbTab & "@ManyToOne(cascade = {CascadeType.PERSIST,CascadeType.MERGE})" &vbCrLf result = result & vbTab & vbTab & "@JoinColumn(name=""" & keyID & """)" & vbCrLf End If AnnotationFK = result End Function Function AnnotationChild(ent As Entity) Dim result As String If Not ent Is Nothing Then result = vbTab & vbTab & "@OneToMany(mappedBy=""" & AttributePrivateName(AttributeName(StrConv(ent.EntityName,vbLowerCase ))) & """)" &vbCrLf End If AnnotationChild = result End Function Function NamespaceStart(entName As String, subModelName As String) Dim result As String result = "//*******************************************" & vbCrLf result = result & "// ** Description: Data Access Object for " & entName & vbCrLf result = result & "// ** Author : Code generator" & vbCrLf result = result & "// ** Created : " & Now & vbCrLf result = result & "// ** Modified :" & vbCrLf result = result & "//*******************************************" & vbCrLf & vbCrLf result = result & "package apps.demo.entity;" & vbCrLf & vbCrLf result = result & "import java.util.*;" & vbCrLf result = result & "import javax.persistence.*;" & vbCrLf result = result & "import core.hibernate.BaseEntity;" & vbCrLf NamespaceStart = result End Function Function FindAttribute(attrs As Attributes, Index As Integer) Dim result As AttributeObj Dim attr As AttributeObj Set result = Nothing For Each attr In attrs If attr.SequenceNumber=Index Then Set FindAttribute=attr Exit Function End If Next Set FindAttribute=Nothing End Function Sub Write2File(fileObj As Object, wordLine As String) fileObj.WriteLine (wordLine) End Sub Const dhcMissing = -2 'sort the entities by name(alphabetic sort) Sub dhQuickSort(varArray As Variant, Optional intLeft As Integer = dhcMissing, Optional intRight As Integer = dhcMissing) Dim i As Integer Dim j As Integer Dim varTestVal As Variant Dim intMid As Integer If intLeft = dhcMissing Then intLeft = LBound(varArray) If intRight = dhcMissing Then intRight = UBound(varArray) If intLeft < intRight Then intMid = (intLeft + intRight) \ 2 varTestVal = UCase(varArray(intMid)) i = intLeft j = intRight Do Do While UCase(varArray(i)) < varTestVal i = i + 1 Loop Do While UCase(varArray(j)) > varTestVal j = j - 1 Loop If i <= j Then SwapElements varArray, i, j i = i + 1 j = j - 1 End If Loop Until i > j If j <= intMid Then Call dhQuickSort(varArray, intLeft, j) Call dhQuickSort(varArray, i, intRight) Else Call dhQuickSort(varArray, i, intRight) Call dhQuickSort(varArray, intLeft, j) End If End If End Sub Private Sub SwapElements(varItems As Variant, intItem1 As Integer, intItem2 As Integer) Dim varTemp As Variant varTemp = varItems(intItem2) varItems(intItem2) = varItems(intItem1) varItems(intItem1) = varTemp End Sub
评论
6 楼
Durian
2009-05-20
面向数据库设计不能使用oo的全部特性。
5 楼
xiaofengtoo
2009-04-13
我比较喜欢楼主的想法。
对于老板与客户不关注那么多,能快速开发,并能实际应用才是最好的东西。
ER的模型设计 可以针对对象的设置,在于怎么使用。
不过这里我有个问题 楼主 ,你能生成出来的文件 是UTF8的文件吗 ?
对于老板与客户不关注那么多,能快速开发,并能实际应用才是最好的东西。
ER的模型设计 可以针对对象的设置,在于怎么使用。
不过这里我有个问题 楼主 ,你能生成出来的文件 是UTF8的文件吗 ?
4 楼
魔力猫咪
2009-03-25
ER的模型是数据库模型不是对象模型。
3 楼
colin4k
2009-03-24
魔力猫咪 写道
不建议使用这种方式。看上去好像方便了,其实是把主次关系搞反了。面向对象设计中对象是核心,不是数据库。如果先设计数据库,然后图省事生成对象,则是面向数据库设计。
ER Studio的模型难道就不是对象?难道必须写成JAVA Class才是对象?
2 楼
kjj
2009-03-24
同意楼上的做法
1 楼
魔力猫咪
2009-03-24
不建议使用这种方式。看上去好像方便了,其实是把主次关系搞反了。面向对象设计中对象是核心,不是数据库。如果先设计数据库,然后图省事生成对象,则是面向数据库设计。
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本压缩包文件"04_JPA详解_第一个JPA实例与JPA主键生成策略.zip"包含了关于如何在实际项目中运用JPA,以及理解JPA主键生成策略的详细教程。 ### JPA基础 1. **JPA简介**: JPA是Java EE的一部分,它提供了一套规范,...
通过以上步骤,你就成功地搭建了JPA环境,并理解了如何创建JPA实体和设置主键生成策略。继续深入学习,你将能够利用JPA的强大功能,如查询语言(JPQL)、级联操作、事务管理等,来更高效地进行数据库操作。
本文将详细介绍如何通过一个简单的员工数据模型来创建、配置、调用并部署一个 SAP JPA 1.0 实体。我们的示例应用仅包含一个实体——“Employee”。该实体允许您执行以下操作:创建新员工、根据唯一标识符查找现有...
当Spring Boot应用启动时,JPA会自动扫描`@Entity`类并根据它们生成对应的数据库表。如果表已存在且与实体类匹配,则不会进行更改。如果表不存在,JPA将根据实体类创建表。 6. **使用Repository** 一旦表创建完成...
数据库 快速生成JPA表对象 脚本
它提供了一种方式,让开发者可以用面向对象的编程模型来操作数据库,而无需直接编写SQL语句。JPA允许你在Java应用程序中以对象的形式处理数据,这些对象可以自动转换为数据库中的记录。 在JPA的例子中,我们通常会...
4. 使用Spring Data JPA的@Entity注解定义Java实体类,对应数据库表结构。 5. 创建一个Repository接口,继承JpaRepository,IDEA会自动生成对应的数据访问方法。 6. 如果数据库已存在,可以使用IDEA的逆向工程工具,...