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所以我试图返回类型“T”数组列表中的最大值,并在使用compareTo时出现错误。这是完整的代码。尝试获取数组中的最大值时出错
package myUtil;
public class SimpleListAry<T extends java.lang.Comparable<T>> extends java.lang.Object implements SimpleList<T> {
private T[] myList;
private int size;
public SimpleListAry(){
myList = (T[])new Comparable[10];
}
public SimpleListAry(int capacity){
if (capacity <= 0){
throw new IllegalArgumentException();
}
myList = (T[]) new Object [capacity];
}
@Override
public int size() {
size = myList.length;
return size;
}
@Override
public T get(int i) {
return myList[i];
}
@Override
public T set(int i, T item) {
return myList[i] = item;
}
@Override
public int indexOf(Object item) {
for (int i = 0; i < size; i++){
if (get(i).equals(item)){
return i;
}
}
return -1;
}
@Override
public void add(int at, T item) {
if (at < 0 || at > size)
throw new ArrayIndexOutOfBoundsException(at);
for (int i = size; i > at; i--){
myList[i] = myList [i-1];
}
// myList[at] = item;
size++;
}
@Override
public T remove(int at) {
if (at < 0 || at >= size)
throw new ArrayIndexOutOfBoundsException(at);
T item = myList[at];
for (int i = at; i<size-1; i++)
myList[i] = myList[i+1];
size--;
return item;
}
@Override
public T max() {
T max = myList[0];
for (int i = 1; i < myList.length; i++){
if(myList[i].compareTo(max) == 1)
max = myList[i];
}
return max;
}
@Override
public T min() {
T min = myList[0];
for (int i = 1; i < size -1; i++){
if (myList[i].compareTo(min) == -1)
min = myList[i];
}
return min;
}
}
,误差在公共t最大():
public T max() {
T max = myList[0];
for (int i = 1; i < myList.length; i++){
if(myList[i].compareTo(max) == 1)
max = myList[i];
}
return max;
}
我也用 “>” 来比较他们尝试但没有工作要么。这可能是因为数据类型的,但有在IDE中没有错误,只有当我尝试运行它,它直接指向这一行t最大(){空指针的
if(myList[i].compareTo(max) == 1)
后错误消息请。 – shmosel
“线程中的异常”main“java.lang.NullPointerException \t at myUtil.SimpleListAry.max(SimpleListAry.java:77)”line 77指向myList.compareTo line –
您正在混淆列表的大小与底层阵列的长度。 – shmosel