模板模式 - ToB企服应用市场:ToB评测及商务社交产业平台

/**
* @author 长名06
* @version 1.0
* 豆浆父类，模板类
*/
public abstract class SoyaMilk {
public final void make(){
select();
add();
soak();
beat();
}
/**
* 选材
*/
public void select(){
System.out.println("第一步，选择黄豆作为材料");
}
/**
* 添加配料
*/
public abstract void add();
/**
* 浸泡
*/
public void soak(){
System.out.println("第三步，黄豆和配料开始浸泡，需要3小时");
}
/**
* 打碎
*/
public void beat(){
System.out.println("第四步，黄豆和配料放到豆浆机去打碎");
}
}
/**
* @author 长名06
* @version 1.0
*/
public class RedBeanSoyaMilk extends SoyaMilk{
@Override
public void add() {
System.out.println("第二步，加入上好的红豆");
}
}
/**
* @author 长名06
* @version 1.0
*/
public class PeanutSoyaMilk extends SoyaMilk {
@Override
public void add() {
System.out.println("第二步，加入上好的花生");
}
}
/**
* @author 长名06
* @version 1.0
*/
public class Client {
public static void main(String[] args) {
//制作红豆豆浆
SoyaMilk redBeanSoyaMilk = new RedBeanSoyaMilk();
redBeanSoyaMilk.make();
System.out.println("----------");
//制作花生豆浆
SoyaMilk peanutSoyaMilk = new PeanutSoyaMilk();
peanutSoyaMilk.make();
}
}

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/**
* @author 长名06
* @version 1.0
* 豆浆父类，模板类
*/
public abstract class SoyaMilk {
public final void make(){
select();
if(isAdd()){
add();
}
soak();
beat();
}
/**
* 选材
*/
public void select(){
System.out.println("第一步，选择黄豆作为材料");
}
/**
* 添加配料
*/
public abstract void add();
/**
* 浸泡
*/
public void soak(){
System.out.println("第三步，黄豆和配料开始浸泡，需要3小时");
}
/**
* 打碎
*/
public void beat(){
System.out.println("第四步，黄豆和配料放到豆浆机去打碎");
}
/**
* 是否需要添加原料，这样设计，可以设置为，子类空实现add步骤，但是不进行添加
* 勾子方法，由这个方法的返回值，判断是否执行那个需要被子类重写的方法，钩子方法
* 是可以被子类继承，由具体子类决定是否执行
* @return
*/
public boolean isAdd(){
return true;
}
}
/**
* @author 长名06
* @version 1.0
*/
public class RedBeanSoyaMilk extends SoyaMilk {
@Override
public void add() {
System.out.println("第二步，加入上好的红豆");
}
}
/**
* @author 长名06
* @version 1.0
* 纯豆浆
*/
public class PureBeanSoyaMilk extends SoyaMilk{
@Override
public void add() {
System.out.println("第二步，制作纯豆浆，不加任何配料");
}
@Override
public boolean isAdd() {
return !super.isAdd();//不执行第二步
}
}
/**
* @author 长名06
* @version 1.0
* 花生豆浆
*/
public class PeanutSoyaMilk extends SoyaMilk {
@Override
public void add() {
System.out.println("第二步，加入上好的花生");
}
}
/**
* @author 长名06
* @version 1.0
*/
public class Client {
public static void main(String[] args) {
//制作红豆豆浆
SoyaMilk redBeanSoyaMilk = new RedBeanSoyaMilk();
redBeanSoyaMilk.make();
System.out.println("----------");
//制作花生豆浆
SoyaMilk peanutSoyaMilk = new PeanutSoyaMilk();
peanutSoyaMilk.make();
System.out.println("----------");
//制作纯豆浆
SoyaMilk pureBeanSoyaMilk = new PureBeanSoyaMilk();
pureBeanSoyaMilk.make();
}
}

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//该方法是AbstractApplicationContext类中的方法，类似模板模式中的模板方法(定义骨架的方法)，案例中的make()
@Override
public void refresh() throws BeansException, IllegalStateException {
//定义容器初始化的模板，空方法由子类实现，由子类调用完成，容器的初始化，AbstractApplicationContext的子类有AbstractRefreshableApplicationContext和
// GenericApplicationContext
synchronized (this.startupShutdownMonitor) {
// Prepare this context for refreshing.
prepareRefresh();
// Tell the subclass to refresh the internal bean factory.
ConfigurableListableBeanFactory beanFactory = obtainFreshBeanFactory();
// Prepare the bean factory for use in this context.
prepareBeanFactory(beanFactory);
try {
// Allows post-processing of the bean factory in context subclasses.
postProcessBeanFactory(beanFactory);
// Invoke factory processors registered as beans in the context.
invokeBeanFactoryPostProcessors(beanFactory);
// Register bean processors that intercept bean creation.
registerBeanPostProcessors(beanFactory);
// Initialize message source for this context.
initMessageSource();
// Initialize event multicaster for this context.
initApplicationEventMulticaster();
// Initialize other special beans in specific context subclasses.
onRefresh();
// Check for listener beans and register them.
registerListeners();
// Instantiate all remaining (non-lazy-init) singletons.
finishBeanFactoryInitialization(beanFactory);
// Last step: publish corresponding event.
finishRefresh();
}
catch (BeansException ex) {
if (logger.isWarnEnabled()) {
logger.warn("Exception encountered during context initialization - " +
"cancelling refresh attempt: " + ex);
}
// Destroy already created singletons to avoid dangling resources.
destroyBeans();
// Reset 'active' flag.
cancelRefresh(ex);
// Propagate exception to caller.
throw ex;
}
finally {
// Reset common introspection caches in Spring's core, since we
// might not ever need metadata for singleton beans anymore...
resetCommonCaches();
}
}
}
//该方法是AbstractApplicationContext类中的方法
protected ConfigurableListableBeanFactory obtainFreshBeanFactory() {
refreshBeanFactory();//这个方法，在本类中是抽象方法，由子类去实现
ConfigurableListableBeanFactory beanFactory = getBeanFactory();
if (logger.isDebugEnabled()) {
logger.debug("Bean factory for " + getDisplayName() + ": " + beanFactory);
}
return beanFactory;
}
//该方法是AbstractApplicationContext类中的方法类似模板模式中的抽象方法，需要子类实现，案例中的add()方法
protected abstract void refreshBeanFactory() throws BeansException, IllegalStateException;

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