的removeAll從列表原因java.lang.UnsupportedOperationException

Question

我想設置successList爲[10,14]什麼，我試圖，

String oneStr = "10,11,12,14"; 
String twoStr = "11,14"; 

Returns r = new Returns(); 

r.setFailureList(Arrays.asList(twoStr.split(","))); 
r.setSuccessList(Arrays.asList(oneStr.split(","))); 

r.getSuccessList().removeAll(r.getFailureList()); 
System.out.println(r.getSuccessList()); 

收益類是，

List<String> successList; 
List<String> failureList; 


public List<String> getSuccessList() { 
    return successList; 
} 
public void setSuccessList(List<String> successList) { 
    this.successList = successList; 
} 
public List<String> getFailureList() { 
    return failureList; 
} 
public void setFailureList(List<String> failureList) { 
    this.failureList = failureList; 
} 
public void setFailureList(ArrayList<String> failureList) { 
    this.failureList = failureList; 
} 

，並導致java.lang.UnsupportedOperationException堆棧跟蹤是，

Exception in thread "main" java.lang.UnsupportedOperationException 
    at java.util.AbstractList.remove(Unknown Source) 
    at java.util.AbstractList$Itr.remove(Unknown Source) 
    at java.util.AbstractCollection.removeAll(Unknown Source) 

Answer 1

從asList()

文檔返回由指定數組支持的固定大小的列表。

所以，當你直接修改（添加，刪除..等）到那個，你最終與exception。

左右，但在案件

new ArrayList<String>(Arrays.asList(twoStr.split(","))) 

在這裏，你是不是指list直接。您正在創建新的ArrayList並使用Arrays.as.asList(twoStr.split(","))返回的列表的數據，而不是Unmodifiable（按大小）。

Answer 2

變化

r.setFailureList(Arrays.asList(twoStr.split(","))); 
r.setSuccessList(Arrays.asList(oneStr.split(","))); 

作爲

r.setFailureList(new ArrayList<String>(Arrays.asList(twoStr.split(",")))); 
r.setSuccessList(new ArrayList<String>(Arrays.asList(oneStr.split(","))));