最l实现的效果代码Q如下所C：
<select>
<option selected="selected" value="Monitor">Monitor</option>
<option value="VCR">VCR</option>
<option value="Standard Device">Standard Device</option>
<option value="Smart Device">Smart Device</option>
<option value="Trunk">Trunk</option>
<option value="Standby VCR">Standby VCR</option>
</select>
2. enum代码
publicenum DeviceType {
@XmlEnumValue("Monitor")
MONITOR("Monitor"),
VCR("VCR"),
@XmlEnumValue("Standard Device")
STANDARD_DEVICE("Standard Device"),
@XmlEnumValue("Smart Device")
SMART_DEVICE("Smart Device"),
@XmlEnumValue("Trunk")
TRUNK("Trunk"),
@XmlEnumValue("Standby VCR")
STANDBY_VCR("Standby VCR");
privatefinal String value;
DeviceType(String v) {
value = v;
}
public String value() {
returnvalue;
}
publicstatic DeviceType fromValue(String v) {
for (DeviceType c: DeviceType.values()) {
if (c.value.equals(v)) {
return c;
}
}
thrownew IllegalArgumentException(v);
}
}
3. JSF标签Q?/span>
<h:selectOneMenu value="#{voutputType.DEVICETYPE}" converter="voutputDeviceTypeConverter">
<f:selectItems value="#{voutput.deviceTypeList}"/>
</h:selectOneMenu>
主要有三个部分组?/span>
(a) value="#{voutputType.DEVICETYPE}"
?/span>javabean ,voutputType中的DEVICETYPE属性，定html代码?/span><option selected="selected" value="Monitor">的?/span>?/span>
voutputType配置信息?/span>"WebRoot"WEB-INF"faces-config.xmlQ?/span>
<managed-bean>
<managed-bean-name>voutputType</managed-bean-name>
<managed-bean-class>
cn.com.gentek.imatrix.xml.jaxb.voutput.ObjVOutputType
</managed-bean-class>
<managed-bean-scope>session</managed-bean-scope>
</managed-bean>
其中DEVICETYPE属性对应的变量是枚?/span>DeviceType的一个实例?/span>
(b) converter="voutputDeviceTypeConverter"
cd转换器，在在"WebRoot"WEB-INF"faces-config.xml配置如下Q?/span>
<converter>
<converter-id>voutputDeviceTypeConverter</converter-id>
<converter-class>
cn.com.gentek.imatrix.ui.VoutDeviceTypeConverter
</converter-class>
</converter>
cn.com.gentek.imatrix.ui.VoutDeviceTypeConverter代码如下Q?/span>
Q实?/span>< select>?/span><option>?/span>Stringcd|?/span>DeviceTypecd之间的{换）
publicclass VoutDeviceTypeConverter implements Converter {
public Object getAsObject(FacesContext context, UIComponent component, String value) {
DeviceType result = null;
if (value == null || value.length() < 1) {
result = null;
} else
result = DeviceType.fromValue(value);
returnresult;
}
public String getAsString(FacesContext context, UIComponent component, Object value) {
String result = null;
if (value != null) {
if (value instanceof DeviceType) {
DeviceType temp = (DeviceType) value;
result = temp.value();
}
}
return result;
}
}
(c) <f:selectItems value="#{voutput.deviceTypeList}"/>Q重点）
׃deviceTypeList对应变量必须?/span>SelectItemQ?/span>javax.faces.model.SelectItemQ列表，所以有必要?/span>DeviceTypecd实例的值和对应Stringcd|装在一?/span>SelectItem实例中。实C码如下：
ArrayList<SelectItem> deviceTypeList = new ArrayList<SelectItem>();
for (int i = 0; i < DeviceType.values().length; i++) {
deviceTypeList.add(new SelectItem(DeviceType.values()[i],
DeviceType.values()[i].value()));
}
]]>
下面通过实例来说明?/span>
首先是介l?/span>webE序目录的大致结构：
D:"......"Tomcat 6.0"webapps"imatrixb ------> E序的更目录
--META-INF
--WEB-INF
---------------classess
---------------------------cn
----------------------------------com
--------------------------------------------…… ----------->class 文g
---------------------------XmlData
---------------------------------path-config.xml Q?/span>1Q?/span>
--------------- path-config.xml Q?/span>2Q?/span>
…….
Index.jsp
一Q?/span>FacesContext
获得Q?/span>2Q号path-config.xml文g信息,
代码如下Q?/span>
String partPath=”/ WEB-INF/ path-config.xml”;
1. getRealPath():
FacesContext
context = FacesContext.getCurrentInstance();
HttpServletRequest rst = (HttpServletRequest)context.getExternalContext().getRequest();
String fullPath=rst.getRealPath(xmlfile); // 获得xml文g的系l\径，xmlfile为相对\?/span>
采用q个Ҏ(gu)存在一些隐(zhn)：比方说对一个打包的应用来说Q是没有RealPath的概늚Q调?/span>getRealPath只会单地q回null?/span>
2. getResourceAsStream():
FacesContext context = FacesContext.getCurrentInstance();
InputStream xmlStream = context.getExternalContext()
.getResourceAsStream(xmlfile);
用于只读的Ş式?/span>
二：ClassLoader
获得Q?/span>1Q号path-config.xml文g信息,
代码如下Q?/span>
String partPath =”/XmlData/path-config.xml”;
String fullPath=this.getClass().getClassLoader().getResource(partPath).getPath();
//使用的时候还是存在一些问题，无法正常使用Q暂时没有发现解决的办法
InputStream xmlStream=this.getClass().getClassLoader().getResourceAsStream(partPath);
//用于只读的Ş式下Q通过试能够正常的?/span>
]]>
1.2.1 学习W记
参考资料：Java 2 核心技?/span>?/span>IQ基知识Q第7版） 5.5 反射
(1) Classc?/span>
在程序运行期_Javaq行时系l始lؓ所有对象的l护一个被UCؓq行时的cd标识。这个信息保存着每一个对象所有属性的cqV虚拟机利用q行信息选择相应的方法执行?/span>
获取Classcd象的三种Ҏ(gu)
(a) getClass()
Employee e;
…
Class cl=e.getClass();
System.out.println(cl.getName()+“ ” +e.getName());
Result:
Employee Harry
(b) forName()
String className= “java.util.Date ”;
Class cl=Class.forName(className);
(c) .class
Class cl1=Date.class;
Class cl2=int.class;
(2) 反射的分析能?/span>
CZQ?/span>
Employee.java:
publicclass Employee {
private String name;
privateintage;
public String getName() {
returnname;
}
publicvoid setName(String name) {
this.name = name;
}
publicint getSalary() {
returnage;
}
publicvoid setSalary(int salary) {
this.age = salary;
}
public Employee(String name, int salary) {
this.name = name;
this.age = salary;
}
}
Test.java
import java.lang.reflect.Field;
publicclass test {
publicstaticvoid main(String[] args) throws SecurityException,
NoSuchFieldException, IllegalArgumentException,
IllegalAccessException {
Employee zhanjh = new Employee("zhan jh", 1000);
Class<?> cl = zhanjh.getClass();
Field f = cl.getDeclaredField("name"); // q回名称?/span>“name”的私有或公有成员Q域Q?/span>
f.setAccessible(true); // 非常重要Q否则无法调?/span>f.get(zhanjh)Ҏ(gu)
Object v = f.get(zhanjh);// q回zhanjh对象?/span> name成员Q域Q的?/span>
System.out.println(v.toString());
}
}
/*
* q行l果Q?/span> zhan jh
*/
]]>
]]>
上午完成thinking Java中关于Interfaces章节的内宏V下面是该章节中关于"Interfaces and factories"的例?br /> package com.zhanjh.thinkingjava.interfaces;
interface Service{
void method1();
void method2();
}
interface ServiceFactory{
Service getService();
}
class Implementation1 implements Service{
public Implementation1() {
// TODO Auto-generated constructor stub
}
public void method1(){
System.out.println("Implementation1 method1");
}
public void method2(){
System.out.println("Implementation1 method2");
}
}
class Implementation1Factory implements ServiceFactory{
public Service getService(){
return new Implementation1();
}
}
class Implementation2 implements Service{
public Implementation2() {
// TODO Auto-generated constructor stub
}
public void method1(){
System.out.println("Implementation2 method1");
}
public void method2(){
System.out.println("Implementation2 method2");
}
}
class Implementation2Factory implements ServiceFactory{
public Service getService(){
return new Implementation2();
}
}
public class Factories{
public static void serviceConsumer(ServiceFactory fact){
Service s=fact.getService();
s.method1();
s.method2();
}
public static void main(String[] args){
serviceConsumer(new Implementation1Factory());
serviceConsumer(new Implementation2Factory());
}
}
ȝQabstract class和interface是Java语言中对于抽象类定义q行支持的两U机Ӟabstract class和interface之间在对于抽象类定义的支持方面具有很大的怼性。目前我对他们区分的Ҏ(gu)大致如下Q?br /> 1Qinterface可以多重实现Q而abstract class只能单一l承
2Qabstract class不一定只有抽象的Ҏ(gu)Qabstract methodQ，它也可以包含具体的方法（concrete methodQ。而interface不能包含Ҏ(gu)的实玎ͼimplementationQ。所以在E序设计的时候，能用inteface的时候尽量不要用abstract class?br />
下午
查找关于EJB的资料，没头l?br /> jaxb入门学习?br /> xjcQ将xsd文g转换为Java的小工具Q工L(fng)使用。可以创Z个bat文g处理下面的命令：
xjc -d "D:"eclipse"workspace"JaxbTest"src" -p "edu.jlu.xml" "D:"eclipse"workspace"JaxbTest"schema"messages.xsd"
其中D:"eclipse"workspace"JaxbTest"src为原文g的目录，edu.jlu.xml为生成Javacȝ包名QD:" eclipse"workspace"JaxbTest"schema"messages.xsd为xml schema文g的\径?br />
]]>