实体引擎（Entity Engine）在OFBiz中是不可或缺的核心组件。本文并不是一篇实体引擎的使用帮助，只是想说明如何独立地去使用实体引擎，可以方便自己阅读源码。笔者将建立一个gradle项目，用来管理依赖。
首先，需要下载OFBiz，可以下载发布包，也可以下载SVN源码。发布包下载地址：http://ofbiz.apache.org/download.html，SVN源码下载：
svn co http://svn.apache.org/repos/asf/ofbiz/trunk ofbiz然后，我们来建gradle项目，创建一个settings.gradle和build.gradle文件：
rootProject.name = 'ofbiz-test-entityengine'
apply plugin: 'java'
apply plugin: 'maven'
project.group = 'com.zf'
project.version = '1.0.0'
project.archivesBaseName = 'ofbiz-test-entityengine'
sourceCompatibility = '1.6'
[compileJava, compileTestJava]*.options*.encoding = 'UTF-8'
if (!hasProperty('mainClass')) {
ext.mainClass = 'com.zf.ofbiz.entity.Main'
}
repositories {
mavenCentral()
mavenLocal()
}
dependencies {
compile fileTree(dir: 'libs', include: '*.jar')
compile (
'commons-codec:commons-codec:1.6'
,'commons-dbcp:commons-dbcp:1.4'
,'commons-lang:commons-lang:2.6'
,'commons-logging:commons-logging:1.1.2'
,'commons-pool:commons-pool:1.3'
,'mysql:mysql-connector-java:5.1.20'
,'log4j:log4j:1.2.17'
,'javolution:javolution:5.4.3'
)
testCompile (
'junit:junit:4.10'
)
}
task sourcesJar(type: Jar, dependsOn: classes, description: 'Creates a jar from the source files.') {
classifier = 'sources'
from sourceSets.main.allSource
}
artifacts {
archives jar
archives sourcesJar
} 可以看到依赖的包有由compile指定的几个，这是在maven仓库里有的；还有一部分是compile fileTree指定的项目libs目录下的所有jar包，主要有：
- antisamy-bin.1.2.jar
- geronimo-transaction-2.1.1.jar
- ofbiz-base.jar
- servlet-api-3.0.jar
- clhm-release-1.0-lru.jar
- icu4j-49_1.jar
- ofbiz-entity.jar
- xercesImpl-2.9.1.jar
- geronimo-j2ee-connector_1.5_spec-1.0.jar
- jakarta-oro-2.0.8.jar
- ofbiz-geronimo.jar
- xstream-1.3.1.jar
- geronimo-jta_1.1_spec-1.1.1.jar
- jdbm-1.0-SNAPSHOT.jar
- owasp-esapi-full-java-1.4.jar
<entitymodel xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://ofbiz.apache.org/dtds/entitymodel.xsd">
<title>Entity of an Open For Business Project Component</title>
<description>None</description>
<version>1.0</version>
<entity package-name="org.zf.entity" entity-name="Party" title="Party Entity" no-auto-stamp="true">
<field name="partyId" type="id-int"></field>
<field name="partyName" type="name"></field>
<prim-key field="partyId"/>
</entity>
<entity package-name="org.zf.entity" entity-name="User" title="User Entity" no-auto-stamp="true">
<field name="userId" type="id-int"></field>
<field name="partyId" type="id-int"></field>
<field name="loginName" type="name"></field>
<prim-key field="userId"/>
</entity>
<view-entity package-name="org.zf.entity.view" entity-name="PartyAndUser" title="Party and User Entity">
<member-entity entity-alias="PARTY" entity-name="Party"/>
<member-entity entity-alias="USER" entity-name="User"/>
<alias-all entity-alias="PARTY"/>
<alias-all entity-alias="USER"/>
<view-link entity-alias="PARTY" rel-entity-alias="USER">
<key-map field-name="partyId" rel-field-name="partyId"/>
</view-link>
</view-entity>
</entitymodel> 除了我们定义的实体外，我们还要配置一下实体引擎，主要配置的是数据库连接、实体配置目录以及数据字段类型。通过文件entityengine.xml定义。
<?xml version="1.0" encoding="UTF-8" ?>
<entity-config xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:noNamespaceSchemaLocation="http://ofbiz.apache.org/dtds/entity-config.xsd">
<resource-loader name="fieldTypeLoader" class="org.ofbiz.base.config.ClasspathLoader" prefix="fieldtype/"/>
<resource-loader name="entityLoader" class="org.ofbiz.base.config.ClasspathLoader" prefix="entity/"/>
<transaction-factory class="org.ofbiz.geronimo.GeronimoTransactionFactory"/>
<connection-factory class="org.ofbiz.entity.connection.DBCPConnectionFactory"/>
<debug-xa-resources value="false" />
<delegator name="default" entity-model-reader="main" entity-group-reader="main" entity-eca-reader="main">
<group-map group-name="org.ofbiz" datasource-name="localmysql"/>
<group-map group-name="org.ofbiz.olap" datasource-name="localmysqlolap"/>
<group-map group-name="org.ofbiz.tenant" datasource-name="localmysqltenant"/>
</delegator>
<!-- 实体配置 -->
<entity-model-reader name="main">
<resource loader="entityLoader" location="entitymodel.xml" />
</entity-model-reader>
<entity-group-reader name="main"/>
<entity-eca-reader name="main"/>
<entity-data-reader name="tenant"/>
<entity-data-reader name="seed"/>
<entity-data-reader name="seed-initial"/>
<entity-data-reader name="demo"/>
<entity-data-reader name="ext"/>
<entity-data-reader name="ext-test"/>
<entity-data-reader name="ext-demo"/>
<!-- 数据类型配置，可以拷贝OFBIZ_HOME/framework/entity/fieldtype/fieldtypemysql.xml文件到项目 -->
<field-type name="mysql" loader="fieldTypeLoader" location="fieldtypemysql.xml"/>
<!-- 数据源配置 -->
<datasource name="localmysql"
helper-class="org.ofbiz.entity.datasource.GenericHelperDAO"
field-type-name="mysql"
check-on-start="true"
add-missing-on-start="true"
check-pks-on-start="false"
use-foreign-keys="true"
join-style="ansi-no-parenthesis"
alias-view-columns="false"
drop-fk-use-foreign-key-keyword="true"
table-type="InnoDB"
character-set="utf8"
collate="utf8_general_cs">
<read-data reader-name="tenant"/>
<read-data reader-name="seed"/>
<read-data reader-name="seed-initial"/>
<read-data reader-name="demo"/>
<read-data reader-name="ext"/>
<read-data reader-name="ext-test"/>
<read-data reader-name="ext-demo"/>
<inline-jdbc
jdbc-driver="com.mysql.jdbc.Driver"
jdbc-uri="jdbc:mysql://localhost/ofbiz?characterEncoding=UTF8"
jdbc-username="ofbiz"
jdbc-password="ofbiz"
isolation-level="ReadCommitted"
pool-minsize="2"
pool-maxsize="250"
time-between-eviction-runs-millis="600000"/>
</datasource>
<datasource name="localmysqlolap"
helper-class="org.ofbiz.entity.datasource.GenericHelperDAO"
field-type-name="mysql"
check-on-start="true"
add-missing-on-start="true"
check-pks-on-start="false"
use-foreign-keys="true"
join-style="ansi-no-parenthesis"
alias-view-columns="false"
drop-fk-use-foreign-key-keyword="true"
table-type="InnoDB"
character-set="utf8"
collate="utf8_general_cs">
<read-data reader-name="tenant"/>
<read-data reader-name="seed"/>
<read-data reader-name="seed-initial"/>
<read-data reader-name="demo"/>
<read-data reader-name="ext"/>
<read-data reader-name="ext-test"/>
<read-data reader-name="ext-demo"/>
<inline-jdbc
jdbc-driver="com.mysql.jdbc.Driver"
jdbc-uri="jdbc:mysql://127.0.0.1/ofbizolap?autoReconnect=true"
jdbc-username="ofbiz"
jdbc-password="ofbiz"
isolation-level="ReadCommitted"
pool-minsize="2"
pool-maxsize="250"
time-between-eviction-runs-millis="600000"/>
</datasource>
<datasource name="localmysqltenant"
helper-class="org.ofbiz.entity.datasource.GenericHelperDAO"
field-type-name="mysql"
check-on-start="true"
add-missing-on-start="true"
check-pks-on-start="false"
use-foreign-keys="true"
join-style="ansi-no-parenthesis"
alias-view-columns="false"
drop-fk-use-foreign-key-keyword="true"
table-type="InnoDB"
character-set="utf8"
collate="utf8_general_cs">
<read-data reader-name="tenant"/>
<read-data reader-name="seed"/>
<read-data reader-name="seed-initial"/>
<read-data reader-name="demo"/>
<read-data reader-name="ext"/>
<read-data reader-name="ext-test"/>
<read-data reader-name="ext-demo"/>
<inline-jdbc
jdbc-driver="com.mysql.jdbc.Driver"
jdbc-uri="jdbc:mysql://127.0.0.1/ofbiztenant?autoReconnect=true"
jdbc-username="ofbiz"
jdbc-password="ofbiz"
isolation-level="ReadCommitted"
pool-minsize="2"
pool-maxsize="250"
time-between-eviction-runs-millis="600000"/>
</datasource>
</entity-config>
这样主要的配置文件都已经有了。对了，还要把OFBIZ_HOME/framework/base/config/cache.properties文件拷贝到项目，也可以再OFBIZ_HOME/framework/base/config/log4j.xml文件到项目目录。下面就是我们的测试代码了：
package com.zf.ofbiz.entity;
import java.util.List;
import org.ofbiz.entity.Delegator;
import org.ofbiz.entity.DelegatorFactory;
import org.ofbiz.entity.GenericValue;
import org.ofbiz.entity.condition.EntityCondition;
public class Main {
public static void main(String[] args) throws Exception {
Delegator delegator = DelegatorFactory.getDelegator("default");
List<GenericValue> valueList = delegator.findList("PartyAndUser", EntityCondition.makeCondition("partyName", "TEST"), null, null, null, true);
System.out.println(valueList.size());
}
}
这样我们就可以独立使用实体引擎了，可以更方便地去测试、学习OFBiz的实体引擎。