importjava.util.Date;publicclassDateDemo01{publicstaticvoidmain(Stringargs[]){Datedate=newDate();//直接实例化Date对象System.out.println("当前日期为："+date);}};importjava.ut...

publicclassSystemDemo01{publicstaticvoidmain(Stringargs[]){longstartTime=System.currentTimeMillis();//取得开始计算之前的时间intsum=0;//声明变量for(inti=0;i<30000000;i++){//...

importjava.util.ResourceBundle;publicclassInterDemo01{publicstaticvoidmain(Stringargs[]){ResourceBundlerb=ResourceBundle.getBundle("Message");//找到资源文件，不用编写后缀Sys...

publicclassRuntimeDemo01{publicstaticvoidmain(Stringargs[]){Runtimerun=Runtime.getRuntime();//通过Runtime类的静态方法进行实例化操作System.out.println("JVM最大内存量："+run.maxMemory...

publicclassStringBufferDemo01{publicstaticvoidmain(Stringargs[]){StringBufferbuf=newStringBuffer();//声明StringBuffer对象buf.append("Hello");//向StringBuffer中添加内容buf...

classInfo{//定义信息类privateStringname="李兴华";//定义name属性privateStringcontent="JAVA讲师";//定义content属性publicvoidsetName(Stringname){this.name=name;}publicvoidsetContent...

classMyThreadimplementsRunnable{privatebooleanflag=true;//定义标志位publicvoidrun(){inti=0;while(this.flag){System.out.println(Thread.currentThread().getName()+"运行，i...

classMyThreadimplementsRunnable{privateintticket=5;//假设一共有5张票publicvoidrun(){for(inti=0;i<100;i++){if(ticket>0){//还有票try{Thread.sleep(300);//加入延迟}catch(In...

classMyThreadextendsThread{privateinttime;publicMyThread(Stringname,inttime){super(name);//设置线程名称this.time=time;//设置休眠时间}publicvoidrun(){try{Thread.sleep(this.t...

classMyThreadimplementsRunnable{//实现Runnable接口publicvoidrun(){//覆写run()方法for(inti=0;i<3;i++){System.out.println(Thread.currentThread().getName()+"运行，i="+i);/...

classMyThreadimplementsRunnable{//实现Runnable接口，作为线程的实现类privateStringname;//表示线程的名称publicMyThread(Stringname){this.name=name;//通过构造方法配置name属性}publicvoidrun(){//覆...

importjava.util.List;importjava.util.ArrayList;publicclassCourse{privateStringname;privateintcredit;privateList<Student>allStudents;publicCourse(){this.al...

importjava.util.List;importjava.util.ArrayList;publicclassSchool{privateStringname;privateList<Student>allStudents;publicSchool(){this.allStudents=newArra...

importjava.util.Properties;publicclassPropertiesDemo01{publicstaticvoidmain(Stringargs[]){Propertiespro=newProperties();//创建Properties对象pro.setProperty("BJ","Be...

importjava.util.Stack;publicclassStackDemo{publicstaticvoidmain(Stringargs[]){Stack<String>s=newStack<String>();s.push("A");//入栈s.push("B");//入栈s.pu...