LinkedList Iterator next（）抛出NoSuchElementException，即使在hasNext（）返回true后调用也是如此

Question

LinkedList Iterator next（）即使在hasNext（）返回true后调用，也会抛出NoSuchElementException。

环境：Sun Solaris上的Java 6

我知道为什么我在next（）方法调用上遇到这个异常？

// lines is an instance of LinkedList
// writer is a FileWriter, Believe that is irrelevant to issue
while(lines.hasNext()){
    int i = 0;
    do {
            writer.write(lines.next());
            writer.newLine();
            i++;
    } while (lines.hasNext() && i < targetLineCount);
    // Some more code... 
}

使用更多代码进行更新

public class MyClass { // Only one instance of this class is used across application
    private List<String> master = new LinkedList<String>();
    // Other instance members to tune this instance behaviour

    public MyClass(){
        // Read Source & populate master
    }

    public boolean writeDataSlot(Writer writer, int targetLineCount){ // Can be called by different Threads
        Ierator<String> lines = master.iterator();
        while(lines.hasNext()){
            int i = 0;
            do {
                writer.write(lines.next());
                writer.newLine();
                i++;
            } while (lines.hasNext() && i < targetLineCount);
            // Some more code to populate slot from different source.
        }
    }
}

Answer 1

我看到了这些可能性：

1. lines用于其他线程
在lines.next() 中调用
2. // some more code...
3. lines绑定到// some more code...
中的另一个实例

Answer 2

正如Axel指出的那样，似乎就像一个线程问题。

如果您使用此方法synchronized会怎样？

public synchronized boolean writeDataSlot(Writer writer, int targetLineCount)