Hexo

学生类: public class Student implements Cloneable{ private String name; private int age; public Student() { } public Student(String name, int age) { this.name = name; this.age = age; } public String getName() { return name; } public void setName(String name) { this.name = name; } public int getAge() { return age; } public void setAge(int age)...

public class runtimeDemon1 { public static void main(String[] args) throws IOException { /* public static Runtime getRuntime()//返回与当前 Java 应用程序相关的运行时对象。 public void exit(int status)//终止当前正在运行的 Java 虚拟机。 public int availableProcessors()//获取cpu线程数 public long maxMemory()//JVM能从系统中获取的总内存大小(单位:Byte) public long totalMemory()//JVM已经从系统中获取的总内存大小(单位:Byte) public long freeMemory()//JVM剩余内存大小(单位:Byte) public process...

public class systemDemon1 { public static void main(String[] args) { /* public static void exit(int status)//终止虚拟机运行 public static long currentTimeMillis//返回当前系统时间差值毫秒值 pubilc status void arraycopy(Object src,int srcPos,Object dest,int destPos,int length)//数组复制(数据源数组,数据源起始索引,目标数组,目标数组起始索引,复制长度) */ //状态码0-正常退出,1-异常退出 System.exit(0); long l=System.currentTimeMillis();//用于判断算法效率 System.out.println(l);//1747193331559 ...

public class mathDemon1 { public static void main(String[] args) { public static int abs(int a)//绝对值 public static double ceil(double a)//向上取整 public static double floor(double a)//向下取整 public static int max(int a,int b)//求最大值 public static int min(int a,int b)//求最小值 public static double pow(double a,double b)//求a的b次幂 public static double random()//求随机数[0.0,1.0) public static int round(float a)//四舍五入 public static double...

验证码获取: public class CodeUtil { public static String getCode(){ ArrayList<Character> list=new ArrayList<>(); for (int i = 0; i < 26; i++) { list.add((char)('a'+i)); list.add((char)('A'+i)); } for(int i=0;i<10;i++){ list.add((char)('0'+i)); } Random r=new Random(); int index; StringBuilder code=new StringBuilder(); ...