Annotation:注解
jdk1.5系统提供了3个Annotation:
1,@Override
在方法覆盖时使用
package com.itheima.annotation;
publicclassAnnotationDemo{
@Override
publicString toSring(){ //覆盖toString方法,由于写错没覆盖,会报错
return"hello";
}
}
2,@Deprecated
表示一个类或者方法不再建议使用
publicclassAnnotationDemo{
@Deprecated
publicvoidsay(){
System.out.println("hello");
}
}
classTest{
publicstaticvoid main(String[] args){
newAnnotationDemo().say();
}
}
3,@SupressWarnings
表示压制警告信息
package com.itheima.annotation;
@SuppressWarnings("deprecation")
publicclassAnnotationDemo{
@Deprecated
publicvoid say(){
System.out.println("hello");
}
}
classTest{
publicstaticvoid main(String[] args){
newAnnotationDemo().say();
}
}
自定义Annotation:
@MyAnnotation(name ="zhangsan",info ="hello")
classTest{
publicstaticvoid main(String[] args){
newAnnotationDemo().say();
}
}
@interfaceMyAnnotation{
publicString name();
publicString info();
}