在此代码中,我收到 java.util.ConcurrentModificationException 该方法位于 Web 服务中,首先读取文件并检查 vakNaam 是否在文件中。然后它将被删除并且文件将被重写。异常由 Exception2 引发(在 println 中)
@WebMethod
public boolean removeVak(String naam){
ArrayList<String> tempFile = new ArrayList<String>();
//Read the lines
boolean found = false;
BufferedReader br = null;
try {
br = new BufferedReader(new FileReader("C:/vak.txt"));
String strLine;
while ((strLine = br.readLine()) != null){
tempFile.add(strLine);
}
}catch(Exception e){
System.out.println("Exception " + e);
}finally {
try {
if (br != null)
br.close();
} catch (Exception ex) {
ex.printStackTrace();
}
}
//Write the lines
BufferedWriter out= null;
try{
for(String s : tempFile){
String [] splitted = s.split(" ");
if(splitted[0].equals(naam)){
tempFile.remove(s);
found = true;
}
}
out = new BufferedWriter(new FileWriter("C:/vak.txt", false));
for(String s: tempFile){
out.newLine();
out.write(s);
}
out.close();
} catch (Exception e) {
System.out.println("Exception2 " + e);
return false;
}finally {
try {
if (out != null)
out.close();
} catch (Exception ex) {
ex.printStackTrace();
}
}
return found;
}
最佳答案
错误在这部分:
for (String s : tempFile){
String [] splitted = s.split(" ");
if (splitted[0].equals(naam)){
tempFile.remove(s);
found = true;
}
}
不要修改您正在迭代的列表。您可以通过显式使用 Iterator
来解决此问题:
for (Iterator<String> it = tempFile.iterator(); it.hasNext();) {
String s = it.next();
String [] splitted = s.split(" ");
if (splitted[0].equals(naam)){
it.remove();
found = true;
}
}
关于java.util.ConcurrentModificationException问题,我们在Stack Overflow上找到一个类似的问题: https://stackoverflow.com/questions/5936501/