源程序:UseArrayList.javaimport java.util.ArrayList;
import java.math.BigInteger;public class UseArrayList
{
public static ArrayList factorial(int x)
{
ArrayList alist=new ArrayList();
alist.add(BigInteger.valueOf(1));
for(int i=alist.size();i<x;i++)
{
BigInteger lastfact=(BigInteger)alist.get(i-1);
BigInteger nextfact=lastfact.multiply(BigInteger.valueOf(i));
alist.add(nextfact);
}
return alist;
} public static void main(String[] args)
{
int x=35;
ArrayList alist=factorial(x);
for(int i=0;i<alist.size();i++)
{
System.out.println(i+"!="+alist.get(i));
}
}
}运行时说:cannot read :UseArrayList.java
import java.math.BigInteger;public class UseArrayList
{
public static ArrayList factorial(int x)
{
ArrayList alist=new ArrayList();
alist.add(BigInteger.valueOf(1));
for(int i=alist.size();i<x;i++)
{
BigInteger lastfact=(BigInteger)alist.get(i-1);
BigInteger nextfact=lastfact.multiply(BigInteger.valueOf(i));
alist.add(nextfact);
}
return alist;
} public static void main(String[] args)
{
int x=35;
ArrayList alist=factorial(x);
for(int i=0;i<alist.size();i++)
{
System.out.println(i+"!="+alist.get(i));
}
}
}运行时说:cannot read :UseArrayList.java
Note:UseArrayList.java uses unchecked or unsafe operations.
Note:Recompile with -Xlint:unchecked for details.
这是什么原因?
Note:UseArrayList.java uses unchecked or unsafe operations.
Note:Recompile with -Xlint:unchecked for details.