异构数组列表

Question

我是"Java noob"，所以请耐心等待:)

我需要创建一个包含异构字段的特定结构。

我正在从 GPS 设备（我的智能手机）获取 Android.Location，我想存储所有位置，但我需要向每个位置添加一些其他字段。所以，我的结构将是这样的：

[0]: Location - String - int - String - int - String - String
[1]: Location - String - int - String - int - String - String
[2]: Location - String - int - String - int - String - String
[3]: Location - String - int - String - int - String - String
[4]: Location - String - int - String - int - String - String
...
[n]: Location - String - int - String - int - String - String

我不知道 "rows" 的数量，因为它取决于一些变量（如时间、路线等）。

在 Java 中哪种方法最好？

更新

这个解决方案正确吗？

public Class LocationPlus {
    private Location location;
    private String string1;
    private int int1;
    private String string2;
    private int int2;

    // Constructor, setters, getters
}

然后，在我的主要：

List<LocationPlus> locationPlus = new ArrayList<LocationPlus>();
locationPlus.add(new LocationPlus(location, “marco”, 1, “bianco”, 2));
locationPlus.add(new LocationPlus(location, “luca”, 3, “arancio”, 4));
locationPlus.add(new LocationPlus(location, “giovanni”, 5, “rossi”, 6));

Answer 1

我认为您最好的选择是创建一个包含所有这些字段（包括 Location）的 class，然后为它们使用合适的 Collection，例如ArrayList.

List<LocationData> locations = new ArrayList<>();

然后在您的自定义 LocationData class 中使用 getter/setter 对来获取您想要存储的每个字段。

自定义class，例如：

public class LocationData {
     //Name these appropriately! I don't know what they're for.
     private Location location;
     private String string1;
     private int num1;
     private String string2;
     private int num2;
     private String string3;
     private String string4;

     //Constructor
     public LocationData(Location loc, String s1, int n1, String s2, int n2, String s3, String s4) {
         location = loc;
         //And so on for each field
         ...
     }

     //One pair of methods for each field
     public Location getLocation() {
         return location;
     }
     public void setLocation(Location loc) {
         location = loc;
     }

Answer 2

我建议使用 ArrayList。这基本上是一个数组（您可以使用它来存储信息）但未设置元素的数量。这意味着您不需要知道 "rows" 的数量。您可以创建类型为另一个数组的 ArrayList。这个数组可以是Object的类型来存储不同类型的变量。

示例：

ArrayList<Object[]> information = new ArrayList<Object[]>();
// The Object[] within the '<>' is the type of the ArrayList
// In this case, the type of the ArrayList happens to be another
// array. This array has a type of Object, meaning almost
// anything can be stored in it.

public void updateInformation(Location loc, String str1, int num1, String str2, int num2, String str3, String str4) {

  int currentSize = 0; // The current size of the ArrayList

  currentSize = information.size(); // Returns the size of the ArrayList

  // Create a new Object array with a size of seven since
  // you have seven pieces of information to store.
  information.add(new Object[7]);

  // For the following, get the newly created Object array,
  // and store your information within the Object array's seven
  // indexes.

  information.get(currentSize)[0] = loc; // Index 0 of Object Array
  information.get(currentSize)[1] = loc; // Index 1 of Object Array
  information.get(currentSize)[2] = loc; // Index 2 of Object Array
  information.get(currentSize)[3] = loc; // Index 3 of Object Array
  information.get(currentSize)[4] = loc; // Index 4 of Object Array
  information.get(currentSize)[5] = loc; // Index 5 of Object Array
  information.get(currentSize)[6] = loc; // Index 6 of Object Array
  // Only go to index six. This is because array SIZES start at 1, but
  // array INDEXES start at 0. This means the max index of an array will
  // always be one less than the size.

}

// The index referring to the index of the ArrayList of the set of
// desired information.
public Object[] getInformation(int index) {

  return information.get(index);
  //  Return the object array with the information

}

异构数组列表

List of heterogenenous array

java

arrays

gps

android

location