如何遍历包含对象的 LinkedList - Java

Question

如何遍历我添加了对象的 LinkedList？

private LinkedList sensors = new LinkedList();
enter code here

//Constructor for my class is taking three arguments
public Sensor(int ID, String Name, String comments) {
    this.ID = ID;
    this.NAME = Name;       
    this.COMMENTS = comments;
}

//Then I query the database to get the values of the variables to create a new Object
ID = Integer.parseInt(dbResult.getString("sensorID") );
        NAME = dbResult.getString("sensorName");    
        COMMENTS = dbResult.getString("sensorcomments");

        //create a new sensor object
        Sensor newSensor = new Sensor(ID, NAME, COMMENTS);

        //add the sensor to the list
        addSensor(newSensor);

` 我遇到的问题是我可以将传感器对象添加到链接列表中，但是当我尝试遍历它时，我得到的是一个引用而不是对象或其值。

//display the results of the Linked List
System.out.println(Arrays.toString(sensors.toArray()));

我得到的输出是 [传感器@4d405ef7，传感器@6193b845，传感器@2e817b38，传感器@c4437c4，传感器@433c675d，传感器@3f91beef]

谢谢

Answer 1

您的 Sensor class 中需要一个 toString() 方法。

@Override
public String toString() {
    return "id: "+ID+"; name: "+NAME+"; comments: "+ COMMENTS;
}

Arrays.toString(Object[] a) 将调用每个 Sensor 对象的 toString() 方法。

这是一个更完整的 Sensor class 示例，其中包含建议的变量名称更改：

class Sensor {

    private int id;
    private String name;
    private String comments;

    public Sensor(int id, String name, String comments) {
        this.id = id;
        this.name = name;       
        this.comments = comments;
    }

    @Override
    public String toString() {
        //You can change how to the string is built in order to achieve your desired output.
        return "id: "+ID+"; name: "+name+"; comments: "+ comment;
    }

}

如何遍历包含对象的 LinkedList - Java

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