component_mapping.pot

hibernate-distribution-3.3.1.GA-dist.zip源码

#. Tag: para
#: component_mapping.xml:149
#, no-c-format
msgid "Of course, there can't be a reference to the purchae on the other side, for bidirectional association navigation. Remember that components are value types and don't allow shared references. A single <literal>Purchase</literal> can be in the set of an <literal>Order</literal>, but it can't be referenced by the <literal>Item</literal> at the same time."
msgstr ""

#. Tag: para
#: component_mapping.xml:157
#, no-c-format
msgid "Even ternary (or quaternary, etc) associations are possible:"
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:159
#, no-c-format
msgid ""
      "<![CDATA[<class name=\"eg.Order\" .... >\n"
      "    ....\n"
      "    <set name=\"purchasedItems\" table=\"purchase_items\" lazy=\"true\">\n"
      "        <key column=\"order_id\">\n"
      "        <composite-element class=\"eg.OrderLine\">\n"
      "            <many-to-one name=\"purchaseDetails class=\"eg.Purchase\"/>\n"
      "            <many-to-one name=\"item\" class=\"eg.Item\"/>\n"
      "        </composite-element>\n"
      "    </set>\n"
      "</class>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:161
#, no-c-format
msgid "Composite elements may appear in queries using the same syntax as associations to other entities."
msgstr ""

#. Tag: title
#: component_mapping.xml:169
#, no-c-format
msgid "Components as Map indices"
msgstr ""

#. Tag: para
#: component_mapping.xml:171
#, no-c-format
msgid "The <literal>&lt;composite-map-key&gt;</literal> element lets you map a component class as the key of a <literal>Map</literal>. Make sure you override <literal>hashCode()</literal> and <literal>equals()</literal> correctly on the component class."
msgstr ""

#. Tag: title
#: component_mapping.xml:180
#, no-c-format
msgid "Components as composite identifiers"
msgstr ""

#. Tag: para
#: component_mapping.xml:182
#, no-c-format
msgid "You may use a component as an identifier of an entity class. Your component class must satisfy certain requirements:"
msgstr ""

#. Tag: para
#: component_mapping.xml:189
#, no-c-format
msgid "It must implement <literal>java.io.Serializable</literal>."
msgstr ""

#. Tag: para
#: component_mapping.xml:194
#, no-c-format
msgid "It must re-implement <literal>equals()</literal> and <literal>hashCode()</literal>, consistently with the database's notion of composite key equality."
msgstr ""

#. Tag: emphasis
#: component_mapping.xml:203
#, no-c-format
msgid "Note: in Hibernate3, the second requirement is not an absolutely hard requirement of Hibernate. But do it anyway."
msgstr ""

#. Tag: para
#: component_mapping.xml:207
#, no-c-format
msgid "You can't use an <literal>IdentifierGenerator</literal> to generate composite keys. Instead the application must assign its own identifiers."
msgstr ""

#. Tag: para
#: component_mapping.xml:212
#, no-c-format
msgid "Use the <literal>&lt;composite-id&gt;</literal> tag (with nested <literal>&lt;key-property&gt;</literal> elements) in place of the usual <literal>&lt;id&gt;</literal> declaration. For example, the <literal>OrderLine</literal> class has a primary key that depends upon the (composite) primary key of <literal>Order</literal>."
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:220
#, no-c-format
msgid ""
      "<![CDATA[<class name=\"OrderLine\">\n"
      "    \n"
      "    <composite-id name=\"id\" class=\"OrderLineId\">\n"
      "        <key-property name=\"lineId\"/>\n"
      "        <key-property name=\"orderId\"/>\n"
      "        <key-property name=\"customerId\"/>\n"
      "    </composite-id>\n"
      "    \n"
      "    <property name=\"name\"/>\n"
      "    \n"
      "    <many-to-one name=\"order\" class=\"Order\"\n"
      "            insert=\"false\" update=\"false\">\n"
      "        <column name=\"orderId\"/>\n"
      "        <column name=\"customerId\"/>\n"
      "    </many-to-one>\n"
      "    ....\n"
      "    \n"
      "</class>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:222
#, no-c-format
msgid "Now, any foreign keys referencing the <literal>OrderLine</literal> table are also composite. You must declare this in your mappings for other classes. An association to <literal>OrderLine</literal> would be mapped like this:"
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:228
#, no-c-format
msgid ""
      "<![CDATA[<many-to-one name=\"orderLine\" class=\"OrderLine\">\n"
      "<!-- the \"class\" attribute is optional, as usual -->\n"
      "    <column name=\"lineId\"/>\n"
      "    <column name=\"orderId\"/>\n"
      "    <column name=\"customerId\"/>\n"
      "</many-to-one>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:230
#, no-c-format
msgid "(Note that the <literal>&lt;column&gt;</literal> tag is an alternative to the <literal>column</literal> attribute everywhere.)"
msgstr ""

#. Tag: para
#: component_mapping.xml:235
#, no-c-format
msgid "A <literal>many-to-many</literal> association to <literal>OrderLine</literal> also uses the composite foreign key:"
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:240
#, no-c-format
msgid ""
      "<![CDATA[<set name=\"undeliveredOrderLines\">\n"
      "    <key column name=\"warehouseId\"/>\n"
      "    <many-to-many class=\"OrderLine\">\n"
      "        <column name=\"lineId\"/>\n"
      "        <column name=\"orderId\"/>\n"
      "        <column name=\"customerId\"/>\n"
      "    </many-to-many>\n"
      "</set>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:242
#, no-c-format
msgid "The collection of <literal>OrderLine</literal>s in <literal>Order</literal> would use:"
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:247
#, no-c-format
msgid ""
      "<![CDATA[<set name=\"orderLines\" inverse=\"true\">\n"
      "    <key>\n"
      "        <column name=\"orderId\"/>\n"
      "        <column name=\"customerId\"/>\n"
      "    </key>\n"
      "    <one-to-many class=\"OrderLine\"/>\n"
      "</set>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:249
#, no-c-format
msgid "(The <literal>&lt;one-to-many&gt;</literal> element, as usual, declares no columns.)"
msgstr ""

#. Tag: para
#: component_mapping.xml:253
#, no-c-format
msgid "If <literal>OrderLine</literal> itself owns a collection, it also has a composite foreign key."
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:258
#, no-c-format
msgid ""
      "<![CDATA[<class name=\"OrderLine\">\n"
      "    ....\n"
      "    ....\n"
      "    <list name=\"deliveryAttempts\">\n"
      "        <key>   <!-- a collection inherits the composite key type -->\n"
      "            <column name=\"lineId\"/>\n"
      "            <column name=\"orderId\"/>\n"
      "            <column name=\"customerId\"/>\n"
      "        </key>\n"
      "        <list-index column=\"attemptId\" base=\"1\"/>\n"
      "        <composite-element class=\"DeliveryAttempt\">\n"
      "            ...\n"
      "        </composite-element>\n"
      "    </set>\n"
      "</class>]]>"
msgstr ""

#. Tag: title
#: component_mapping.xml:263
#, no-c-format
msgid "Dynamic components"
msgstr ""

#. Tag: para
#: component_mapping.xml:265
#, no-c-format
msgid "You may even map a property of type <literal>Map</literal>:"
msgstr ""

#. Tag: programlisting
#: component_mapping.xml:269
#, no-c-format
msgid ""
      "<![CDATA[<dynamic-component name=\"userAttributes\">\n"
      "    <property name=\"foo\" column=\"FOO\" type=\"string\"/>\n"
      "    <property name=\"bar\" column=\"BAR\" type=\"integer\"/>\n"
      "    <many-to-one name=\"baz\" class=\"Baz\" column=\"BAZ_ID\"/>\n"
      "</dynamic-component>]]>"
msgstr ""

#. Tag: para
#: component_mapping.xml:271
#, no-c-format
msgid "The semantics of a <literal>&lt;dynamic-component&gt;</literal> mapping are identical to <literal>&lt;component&gt;</literal>. The advantage of this kind of mapping is the ability to determine the actual properties of the bean at deployment time, just by editing the mapping document. Runtime manipulation of the mapping document is also possible, using a DOM parser. Even better, you can access (and change) Hibernate's configuration-time metamodel via the <literal>Configuration</literal> object."
msgstr ""