自定义异常

classNewExceptionextendsOldException{
......
}

三角形边长为负值异常classTriangleMinusLengthExceptionextendsException{
Stringname;
publicTriangleMinusLengthException(Stringstr)
    { 
name=str;
    }
publicStringtoString()
    {
returnname;
  }
}

不满足三角不等式异常classTriangleUnequationExceptionextendsException{
Stringname;
publicTriangleUnequationException (Stringstr)
    {
name=str;
    }
publicStringtoString()
    {
returnname;
  }
}