-- Start
如果沒有显示给域赋初值, 那么它会被自动赋初始值, 数值为0, 布尔值为false, 对象为null. 值得注意的是我们在使用局部变量之前, 必须明确的初始化局部变量, 否则编译会报错.
private byte b; private short s; private int i; private long l; private float f; private double d; private char c; private boolean bl; private String str; public Test() { System.out.println("byte 域的默认值是 " + b); System.out.println("short 域的默认值是 " + s); System.out.println("int 域的默认值是 " + i); System.out.println("long 域的默认值是 " + l); System.out.println("float 域的默认值是 " + f); System.out.println("double 域的默认值是 " + d); System.out.println("char 域的默认值是 " + c); System.out.println("boolean 域的默认值是 " + bl); System.out.println("Object 域的默认值是 " + str); byte bLocal; //System.out.println("byte 局部变量的值是 " + bLocal); // 编译错误 }
结果如下:
byte 域的默认值是 0 short 域的默认值是 0 int 域的默认值是 0 long 域的默认值是 0 float 域的默认值是 0.0 double 域的默认值是 0.0 char 域的默认值是
---更多参见:Java 精萃
-- 声 明:转载请注明出处
-- Last Updated on 2012-05-17
-- Written by ShangBo on 2012-05-17
-- End