我有一个简单的问题:
在Java编译器中,可以将哪种类型的方法或变量定义为标识符(ID)或关键字(保留字)?
对于以下示例,ID应该是:add
,main
,a
,b
,c
,Test1
,print
怎么样?print
是ID还是关键字?
例:
public class Test1 {
public static int add(int a, int b) {
return a + b;
}
public static void main() {
int c;
int a = 5;
c = add(a, 10);
if (c > 10)
print("c = " + -c);
else
print(c);
print("Hello World");
}
}
最佳答案
标识符是程序员用来命名变量,方法,类或标签的单词。
// Test1 is a class name identifier
public class Test1 {
public static int add(int a, int b) { // add is identifier for a method
return a + b;
}
public static void main() {
int c; // c is identifier for a variable
int a = 5;
c = add(a, 10);
if (c > 10)
print("c = " + -c);
else
print(c);
print("Hello World");
}
}
您在Java程序中
cannot use
任何Keywords as identifiers
您上面的程序中的
print
不是Keyword
,您可以将print用作identifier
使用print作为标识符后,您的代码如下所示。
//Test1 is a class name identifier
public class Test1 {
// add is identifier for a method
public static int add(int a, int b) {
return a + b;
}
public static void main(String[] args) {
int c; // c is identifier for a variable
int a = 5;
c = add(a, 10);
if (c > 10)
print("c = " + -c); // c is a String
else
print(c); // c is a int
print("Hello World"); // Hello World is a String
}
/**
* Method Overriding
*/
private static void print(int c) {
System.out.println("In Integer Print Method "+c);
}
private static void print(String string) {
System.out.println("In String Print Method "+string);
}
}
另请参阅:
Check Legal Identifiers in java @Peter Lawrey
List of Keywords and Reserved Words in java