Changes between Version 23 and Version 24 of waue/2011/spring

Timestamp:

Aug 26, 2011, 5:13:35 PM (13 years ago)

Author:

waue

Comment:

--

waue/2011/spring

@@ -425 +425 @@
 
 
-
-
-
-
+ == 不用 xml 綁值 == 
+
+假設HelloBean的內容如下：
+
+ * HelloBean.java
+{{{
+#!java
+package onlyfun.caterpillar; 
+
+public class HelloBean { 
+    private String helloWord;
+    
+    public HelloBean() {
+    }
+    
+    public void setHelloWord(String helloWord) { 
+        this.helloWord = helloWord;
+    } 
+    public String getHelloWord() { 
+        return helloWord; 
+    }
+}
+}}}
+
+ === 使用 properties ===
+XML檔案的階層格式適用於於組態設定，也因此許多的開源專案都將XML作為預設的組態定義方式，但通常也會提供非XML定義檔的方式，像屬性檔案. properties，Spring也可以讓您使用屬性檔案定義Bean，例如定義一個beans-config.properties：
+
+ * beans-config.properties
+{{{
+#!java
+helloBean.class=onlyfun.caterpillar.HelloBean
+helloBean.helloWord=Welcome!
+}}}
+
+屬性檔中helloBean名稱即是Bean的名稱，.class用於指定類別來源，其它的屬性就如.helloWord即屬性的名稱，可以使用 org.springframework.beans.factory.support.PropertiesBeanDefinitionReader 來讀取屬性檔，一個範例如下：
+
+ * SpringDemo.java
+
+{{{
+#!java
+package onlyfun.caterpillar; 
+
+import org.springframework.beans.factory.BeanFactory;
+import org.springframework.beans.factory.support.BeanDefinitionRegistry;
+import org.springframework.beans.factory.support.DefaultListableBeanFactory;
+import org.springframework.beans.factory.support.PropertiesBeanDefinitionReader; 
+import org.springframework.core.io.ClassPathResource;
+
+public class SpringDemo { 
+    public static void main(String[] args) { 
+        BeanDefinitionRegistry reg = 
+            new DefaultListableBeanFactory(); 
+        PropertiesBeanDefinitionReader reader = 
+            new PropertiesBeanDefinitionReader(reg); 
+        reader.loadBeanDefinitions(
+                new ClassPathResource("beans-config.properties")); 
+        
+        BeanFactory factory = (BeanFactory) reg; 
+        HelloBean hello = (HelloBean) factory.getBean("helloBean"); 
+        System.out.println(hello.getHelloWord()); 
+    } 
+}
+}}}
+
+ === 直接綁值 ===
+
+不用 xml , 也不用 properties 來設定值
+
+好處是，客戶端與定義檔是隔離的，他們無法接觸定義檔的內容，直接來看個例子：
+
+ * SpringDemo.java
+
+{{{
+#!java
+
+package onlyfun.caterpillar; 
+
+import org.springframework.beans.factory.support.BeanDefinitionRegistry; 
+import org.springframework.beans.factory.support.DefaultListableBeanFactory; 
+import org.springframework.beans.factory.support.RootBeanDefinition; 
+import org.springframework.beans.factory.BeanFactory; 
+import org.springframework.beans.MutablePropertyValues; 
+
+public class SpringDemo { 
+    public static void main(String[] args) { 
+        // 設置屬性 
+        MutablePropertyValues properties = new MutablePropertyValues(); 
+        properties.addPropertyValue("helloWord", "Hello!Justin!"); 
+        
+        // 設置Bean定義 
+        RootBeanDefinition definition = 
+                    new RootBeanDefinition(HelloBean.class, properties); 
+        
+        // 註冊Bean定義與Bean別名 
+        BeanDefinitionRegistry reg = new DefaultListableBeanFactory(); 
+        reg.registerBeanDefinition("helloBean", definition); 
+        
+        BeanFactory factory = (BeanFactory) reg;        
+        HelloBean hello = (HelloBean) factory.getBean("helloBean"); 
+        System.out.println(hello.getHelloWord()); 
+    } 
+}
+}}}