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import java.util.ArrayList;  
import java.util.List;  
public class Test {  
    public static void main(String[] args) {  
          
        List<String> list = new ArrayList<String>();   
        list.add("1");   
        list.add("2");   
        String[] tt =(String[]) list.toArray(new String[0]);   
    }  
}
 
Õâ¶Î´úÂëÊÇûÎÊÌâµÄ£¬µ«ÎÒÃÇ¿´µ½String[] tt =(String[]) list.toArray(new String[0]) ÖеIJÎÊýºÜÆæ¹Ö£¬È»¶øÈ¥µôÕâ¸ö²ÎÊýnew String[0]È´ÔÚÔËÐÐʱ±¨´í¡£¡£¡£
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public Object[] toArray() {  
   Object[] result = new Object[size];     
   System.arraycopy(elementData, 0, result, 0, size);     
   return result;  
}  
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public Object[] toArray(Object a[]) {     
if (a.length < size)         
a = (Object[])java.lang.reflect.Array.newInstance(a.getClass().getComponentType(), size);       System.arraycopy(elementData, 0, a, 0, size);     
if (a.length > size)         
a[size] = null;     
return a;  
}
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public class Test1{
    public static void main(String[] args){
        System.out.println(2.0 - 1.1);
    }
}
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public class Test2{
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