java.lang.indexoutofboundsexception 索引 0 大小 0
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提问by rez
I've been getting this java.lang.indexoutofboundsexception error when adding system functions objects in an array through checkbox:
通过复选框在数组中添加系统函数对象时，我遇到了这个 java.lang.indexoutofboundsexception 错误：
SEVERE: Servlet.service() for servlet spis threw exception
java.lang.IndexOutOfBoundsException: Index: 0, Size: 0
at java.util.ArrayList.rangeCheck(ArrayList.java:604)
at java.util.ArrayList.get(ArrayList.java:382)
at com.spis.dao.impl.CodesValueDaoImpl.getDescription(CodesValueDaoImpl.java:95)
at com.spis.bo.impl.CodesValueBoImpl.getDescription(CodesValueBoImpl.java:103)
at com.spis.controller.SystemUserController.viewPaged(SystemUserController.java:408)
at com.spis.controller.SystemUserController.systemUser(SystemUserController.java:48)
Here is the for the systemFunctions: whenever i add systemFunction to a user it displays the error or when the systemFunction colummn in the database is null. But when i set systemFunction=" " in the database the page displays correctly although withouth the array of systemFunctions obviously..
以下是 systemFunctions：每当我向用户添加 systemFunction 时，它都会显示错误，或者当数据库中的 systemFunction 列为空时。但是当我在数据库中设置 systemFunction="" 时，页面显示正确，尽管显然没有 systemFunctions 数组..
String[] systemFunctions=(String[])request.getParameterValues("systemFunctions");
String appendedSysFunctions ="";
//Append system functions
if(systemFunctions!=null){
for(int i=0;i<systemFunctions.length;i++){
if(i==(systemFunctions.length-1)){
appendedSysFunctions+=systemFunctions[i];
}
else{
appendedSysFunctions+=systemFunctions[i] + ",";
}
}
}
Another code:
另一个代码：
StringTokenizer st = new StringTokenizer(su.getAllowedSysFunc(), ",");
while (st.hasMoreTokens()){
appendedSystemFunc = appendedSystemFunc + codesValueMethods.getDescription
(3, st.nextToken());
if(st.hasMoreTokens()){
appendedSystemFunc = appendedSystemFunc + ", \n";
}
}
回答by Omoro
You have to check systemFunctionswhether it is null and whether its length is greater than 0:
您必须检查systemFunctions它是否为空以及其长度是否大于 0：
if(systemFunctions!=null && systemFunctions.length>0){
...
}
