• 注入null

# 方式一：可以在實體類中直接設定為空
private String oname="";

# 方式二：在bean.xml中配置如下
<property name="address">
    <null/>
</property>

• 測試

# 實體類
public class Book {

    private String bname;

    private String bauthor;

    private String address;

    public void setBname(String bname) {
        this.bname = bname;
    }
    public void setBauthor(String bauthor) {
        this.bauthor = bauthor;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public void testDemo() {
        System.out.println(bname+"::"+bauthor+"::"+address);
    }

}

# bean.xml
    <bean id="book" class="com.ychen.spring.model.Book">
        <property name="bname" value="易筋經"></property>
        <property name="bauthor" value="達摩老祖"></property>
        <property name="address">
            <null/>
        </property>
    </bean>

# 測試方法
    @Test
    public void testBook1() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        Book book = context.getBean("book", Book.class);
        System.out.println(book);
        book.testDemo();
    }

# 測試
com.ychen.spring.model.Book@19932c16
易筋經::達摩老祖::null
 

• 注入特殊字元，直接寫在value屬性中會報錯

# 方式一：使用轉義字元，例如&lt; &gt;就表示 < >
# 方式二：把帶特殊符號內容寫到 CDATA

• 測試：把帶特殊符號內容寫到 CDATA

# 實體
public class Book {

    private String bname;

    private String bauthor;

    private String address;

    public void setBname(String bname) {
        this.bname = bname;
    }
    public void setBauthor(String bauthor) {
        this.bauthor = bauthor;
    }

    public void setAddress(String address) {
        this.address = address;
    }

    public void testDemo() {
        System.out.println(bname+"::"+bauthor+"::"+address);
    }

}

# bean.xml
    <bean id="book" class="com.ychen.spring.model.Book">
        <property name="bname" value="易筋經"></property>
        <property name="bauthor" value="達摩老祖"></property>
        <property name="address">
            <value><![CDATA[<<南京>>]]></value>
        </property>
    </bean>

# 測試方法
    @Test
    public void testBook1() {
        ApplicationContext context =
                new ClassPathXmlApplicationContext("bean1.xml");
        Book book = context.getBean("book", Book.class);
        System.out.println(book);
        book.testDemo();
    }

# 測試
com.ychen.spring.model.Book@305ffe9e
易筋經::達摩老祖::<<南京>>

Process finished with exit code 0