因为static 方法不需它所属的类的任何实例就会被调用,因此没有 this 值。结果是,static方法不能访问与它本身的参数以及 static 变量之外的任何变量,访问非静态变量的尝试会引起编译错误。 注:非静态变量只限于实例,并只能通过实例引用被访问。 四.静态初始器——静态块 静态初始器(Static Initializer)是一个存在与...
静态初始器(Static Initializer)是一个存在于类中、方法外面的静态块。静态初始器仅仅在类装载的时候(第一次使用类的时候)执行一次,往往用来初始化静态变量。 示例代码: 1publicclassDemo {2publicstaticinti;3static{4i = 10;5System.out.println("Now in static block.");6}7publicvoidtest() {8System.out...
public class Whatever {private static double money = 9;private int age = 9;{System.out.println("2.Initializer 初始化块");money = 2;age = 888;}private Whatever() {System.out.println("3.Constructor 构造器");}static {System.out.println("1.Static 静态初始化块");money = 1;// ERROR: N...
在实际开发中,我们要注意静态变量的初始化顺序,并尽量避免出现这种问题。 类图 下面是Config类的类图: Config- static String property+static String getProperty()+static void init() 参考资料 [Java Language Specification - Chapter 12.4.2]( [Java static initializer block](...
MyInterface.java:2: error: interface cannot have static initializer static { ^ 1 error 这表明了...
publicclassStaticInitializerExample{privatestaticintstaticVar;// 静态初始化块static{staticVar=42;System.out.println("Static block executed: staticVar initialized to "+staticVar);}publicstaticvoiddisplay(){System.out.println("Value of staticVar: "+staticVar);}publicstaticvoidmain(String[]args){Static...
在Java中，静态初始化块(static initializer block)是在类加载时执行的，而不是在实例化对象时执行的。
public static void main(String args[]){ InstanceInitializerBlockDemo i1=new InstanceInitializerBlockDemo(); InstanceInitializerBlockDemo i2=new InstanceInitializerBlockDemo(2); } } In the above program, we see that the constructor of the parent class is invoked first then instance initializer bloc...
3. Initializer Blocks Run in Sequence If there are multiple initializer blocks in a class, they are executed in the same sequence they appear in the class definition. In following example, the initializer block 1 executes before block 2, always. ...
public staticvoid main(String[]args) { ExceptionExample instance1 = newExceptionExample(); instance1.testMethod1(); } } 运行上面的程序,将抛出以下异常: java.io.EOFException at java.io.DataInputStream.readInt(DataInputStream.java:392) at logging.simple.ExceptionExample.testMethod1(ExceptionExample...