在EJB出错？

Question

你的jndi有问题，如果你用的是weblogic平台，进入你的控制台看看你的jndi
树中有没有User,如果没有，则修改你的ejb-jar.xml文件，并重新部署。

Answer 1

楼上说的对，你的jndi名称与你程序中的不一样啊。

Answer 2

明显是jnid有问题，
请问你部署的ejb的文件结构
有没有一个
weblogic-ejb-jar.xml这个文件的
里面又有没有
<jndi-name>User</jndi-name>
这么一行？

Answer 3

我用的是ESite的例子
有这么一行？
<jndi-name>User</jndi-name>
weblogic-ejb-jar.xml
///-----------------
<?xml version="1.0" encoding="UTF-8"?>
<!DOCTYPE weblogic-ejb-jar PUBLIC '-//BEA Systems, Inc.//DTD WebLogic 6.0.0 EJB//EN' 'http://www.bea.com/servers/wls600/dtd/weblogic-ejb-jar.dtd'>
<weblogic-ejb-jar>
<weblogic-enterprise-bean>
<ejb-name>Cart</ejb-name>
<reference-descriptor>
<ejb-reference-description>
<ejb-ref-name>ejb/ServerDataModule</ejb-ref-name>
<jndi-name>ServerDataModule</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/User</ejb-ref-name>
<jndi-name>User</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/ShoppingCart</ejb-ref-name>
<jndi-name>ShoppingCart</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/Order</ejb-ref-name>
<jndi-name>Order</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/Orderitem</ejb-ref-name>
<jndi-name>Orderitem</jndi-name>
</ejb-reference-description>
</reference-descriptor>
<jndi-name>Cart</jndi-name>
</weblogic-enterprise-bean>
<weblogic-enterprise-bean>
<ejb-name>ServerDataModule</ejb-name>
<reference-descriptor>
<resource-description>
<res-ref-name>jdbc/DataSource</res-ref-name>
<jndi-name>DataSource</jndi-name>
</resource-description>
<ejb-reference-description>
<ejb-ref-name>ejb/Inventory</ejb-ref-name>
<jndi-name>Inventory</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/ShoppingCart</ejb-ref-name>
<jndi-name>ShoppingCart</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/User</ejb-ref-name>
<jndi-name>User</jndi-name>
</ejb-reference-description>
<ejb-reference-description>
<ejb-ref-name>ejb/Order</ejb-ref-name>
<jndi-name>Order</jndi-name>
</ejb-reference-description>
</reference-descriptor>
<jndi-name>ServerDataModule</jndi-name>
</weblogic-enterprise-bean>
<weblogic-enterprise-bean>
<ejb-name>User</ejb-name>
<entity-descriptor>
            <persistence>
                <persistence-type>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                    <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
                </persistence-type>
                <persistence-use>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                </persistence-use>
            </persistence>
        </entity-descriptor>
        <reference-descriptor>
            <resource-description>
                <res-ref-name>jdbc/DataSource</res-ref-name>
                <jndi-name>DataSource</jndi-name>
            </resource-description>
        </reference-descriptor>
        <jndi-name>User</jndi-name>
    </weblogic-enterprise-bean>
    <weblogic-enterprise-bean>
        <ejb-name>Inventory</ejb-name>
        <entity-descriptor>
            <persistence>
                <persistence-type>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                    <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
                </persistence-type>
                <persistence-use>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                </persistence-use>
            </persistence>
        </entity-descriptor>
        <reference-descriptor>
            <resource-description>
                <res-ref-name>jdbc/DataSource</res-ref-name>
                <jndi-name>DataSource</jndi-name>
            </resource-description>
        </reference-descriptor>
        <jndi-name>Inventory</jndi-name>
    </weblogic-enterprise-bean>
    <weblogic-enterprise-bean>
        <ejb-name>ShoppingCart</ejb-name>
        <entity-descriptor>
            <persistence>
                <persistence-type>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                    <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
                </persistence-type>
                <persistence-use>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                </persistence-use>
            </persistence>
        </entity-descriptor>
        <reference-descriptor>
            <resource-description>
                <res-ref-name>jdbc/DataSource</res-ref-name>
                <jndi-name>DataSource</jndi-name>
            </resource-description>
            <ejb-reference-description>
                <ejb-ref-name>ejb/Inventory</ejb-ref-name>
                <jndi-name>Inventory</jndi-name>
            </ejb-reference-description>
        </reference-descriptor>
        <jndi-name>ShoppingCart</jndi-name>
    </weblogic-enterprise-bean>
    <weblogic-enterprise-bean>
        <ejb-name>Order</ejb-name>
        <entity-descriptor>
            <persistence>
                <persistence-type>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                    <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
                </persistence-type>
                <persistence-use>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                </persistence-use>
            </persistence>
        </entity-descriptor>
        <reference-descriptor>
            <resource-description>
                <res-ref-name>jdbc/DataSource</res-ref-name>
                <jndi-name>DataSource</jndi-name>
            </resource-description>
            <ejb-reference-description>
                <ejb-ref-name>ejb/Orderitem</ejb-ref-name>
                <jndi-name>Orderitem</jndi-name>
            </ejb-reference-description>
        </reference-descriptor>
        <jndi-name>Order</jndi-name>
    </weblogic-enterprise-bean>
    <weblogic-enterprise-bean>
        <ejb-name>Orderitem</ejb-name>
        <entity-descriptor>
            <persistence>
                <persistence-type>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                    <type-storage>META-INF/weblogic-cmp-rdbms-jar.xml</type-storage>
                </persistence-type>
                <persistence-use>
                    <type-identifier>WebLogic_CMP_RDBMS</type-identifier>
                    <type-version>5.1.0</type-version>
                </persistence-use>
            </persistence>
        </entity-descriptor>
        <reference-descriptor>
            <resource-description>
                <res-ref-name>jdbc/DataSource</res-ref-name>
                <jndi-name>DataSource</jndi-name>
            </resource-description>
            <ejb-reference-description>
                <ejb-ref-name>ejb/Order</ejb-ref-name>
                <jndi-name>Order</jndi-name>
            </ejb-reference-description>
        </reference-descriptor>
        <jndi-name>Orderitem</jndi-name>
    </weblogic-enterprise-bean>
</weblogic-ejb-jar>

Answer 4

try {
Object object = context.lookup("User");
}
catch (Exception e)
{
e.printStackTrace()
}