/**
     * 使用增强的for循环
     * 在循环过程中从List中删除元素以后，继续循环List时会报ConcurrentModificationException
     */
    public void listRemove() {
        List<Student> students = this.getStudents();
        for (Student stu : students) {
            if (stu.getId() == 2) 
                students.remove(stu);
        }
    }

    /**
     * 像这种使用增强的for循环对List进行遍历删除，但删除之后马上就跳出的也不会出现异常
     */
    public void listRemoveBreak() {
        List<Student> students = this.getStudents();
        for (Student stu : students) {
            if (stu.getId() == 2) {
                students.remove(stu);
                break;
            }
        }
    }

    /**
     * 这种遍历有可能会遗漏某个元素,因为删除元素后List的size在
     * 变化，元素的索引也在变化，比如你循环到第2个元素的时候你把它删了，
     * 接下来你去访问第3个元素，实际上访问到的是原先的第4个元素。当访问的元素
     * 索引超过了当前的List的size后还会出现数组越界的异常，当然这里不会出现这种异常，
     * 因为这里每遍历一次都重新拿了一次当前List的size。
     */
    public void listRemove2() {
        List<Student> students = this.getStudents();
        for (int i=0; i<students.size(); i++) {
            if (students.get(i).getId()%3 == 0) {
                Student student = students.get(i);
                students.remove(student);
            }
        }
    }

    /**
     * 使用Iterator的方式也可以顺利删除和遍历
     */
    public void iteratorRemove() {
        List<Student> students = this.getStudents();
        System.out.println(students);
        Iterator<Student> stuIter = students.iterator();
        while (stuIter.hasNext()) {
            Student student = stuIter.next();
            if (student.getId() % 2 == 0)
//这里要使用Iterator的remove方法移除当前对象，如果使用List的remove方法，则同样会出现ConcurrentModificationException
                stuIter.remove();
        }
        System.out.println(students);
    }

import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

public class ListRemove {

    public static void main(String args[]) {
        ListRemove lr = new ListRemove();
        lr.listRemove();
        lr.listRemoveBreak();
//        lr.listRemove2();
//        lr.iteratorRemove();
    }

    /**
     * 使用增强的for循环
     * 在循环过程中从List中删除元素以后，继续循环List时会报ConcurrentModificationException
     */
    public void listRemove() {
        List<Student> students = this.getStudents();
        for (Student stu : students) {
            if (stu.getId() == 2) 
                students.remove(stu);
        }
    }
    
    /**
     * 像这种使用增强的for循环对List进行遍历删除，但删除之后马上就跳出的也不会出现异常
     */
    public void listRemoveBreak() {
        List<Student> students = this.getStudents();
        for (Student stu : students) {
            if (stu.getId() == 2) {
                students.remove(stu);
                break;
            }
        }
    }
    
    /**
     * 这种不使用增强的for循环，每次重新获取list的size遍历的情况运行时不会报错，但是可能删除的结果是错的。
     */
    public void listRemove2() {
        List<Student> students = this.getStudents();
        for (int i=0; i<students.size(); i++) {
            if (students.get(i).getId()%2 == 0)
                students.remove(i);
        }
    }
    
    /**
     * 使用Iterator的方式也可以顺利删除和遍历
     */
    public void iteratorRemove() {
        List<Student> students = this.getStudents();
        System.out.println(students);
        Iterator<Student> stuIter = students.iterator();
        while (stuIter.hasNext()) {
            Student student = stuIter.next();
            if (student.getId() % 2 == 0)
                stuIter.remove();
        }
        System.out.println(students);
    }
    
    private List<Student> getStudents() {
        List<Student> students = new ArrayList<Student>() {
            {
                int i = 0;
                while (i++ < 10) {
                    Student student = new Student(i, "201200" + i, "name_" + i);
                    this.add(student);
                }
            }
        };
        return students;
    }
}

public class Student {

    private int id;
    private String stuNo;
    private String name;
    
    public Student() {
        
    }
    
    public Student(int id, String stuNo, String name) {
        this.id = id;
        this.stuNo = stuNo;
        this.name = name;
    }

    public int getId() {
        return id;
    }

    public void setId(int id) {
        this.id = id;
    }

    public String getStuNo() {
        return stuNo;
    }

    public void setStuNo(String stuNo) {
        this.stuNo = stuNo;
    }

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    @Override
    public String toString() {
        return "Student [id=" + id + ", name=" + name + ", stuNo=" + stuNo
                + "]";
    }
    
}