Java 按列表中的指定值对ArrayList排序
例如，我有一个数组：Java 按列表中的指定值对ArrayList排序,java,arrays,sorting,arraylist,Java,Arrays,Sorting,Arraylist,例如，我有一个数组： String[] Array1 = {"15", "1", "D1", "Wine", "1", "0", "15", "3", "D3", "Tap water", "2", "2", "15", "1", "M1", "Fish", "3", "0", "9", "5", "D4", "Coffee", "2", "2", "9", "2", "
String[] Array1 =
{"15", "1", "D1", "Wine", "1", "0",
"15", "3", "D3", "Tap water", "2", "2",
"15", "1", "M1", "Fish", "3", "0",
"9", "5", "D4", "Coffee", "2", "2",
"9", "2", "P2", "Cake", "2", "1"
};
someList.addAll(Arrays.asList(Array1));
我想根据每行中的第二个值，即1,3,1,5,2，将类似于此的某种类型的ArrayList按数字顺序排序为1,1,2,3,5，同时保持同一行中的其他变量不变。我不允许创建另一个类来按顺序存储这些变量。有人知道我如何对它们进行那样的排序吗？您使用了错误的数据结构。数组用于包含相同类型信息的相同类型的多个变量 我建议您创建一个类，并创建一个包含该类对象的数组，如下所示： 喝酒。上课
class Drink{
private int a;
private int b;
private String c;
private String drinkName;
private int d;
private int e;
public Drink(int a,int b,String c,String drinkName,int d,int e){
this.a=a;
this.b=b;
this.c=c;
this.drinkName=drinkName;
this.d=d;
this.e=e;
}
// Getters and setters here
public String getDrinkName(){
return drinkName;
}
// .....
}
class MainClass{
List<Drink> drinks;
public static void main(String[] args){
drinks = new ArrayList<>();
drinks.add(new Drink(15,1,"D1","Wine",1,0));
drinks.add(new Drink(15,3,"D3","Tap Water",2,2));
// Etc...
// You can retrieve elements using .get(index) and then use getters on it to retrieve informations
System.out.println(drinks.get(0).getDrinkName());
Collections.sort(drinks,new Comparator<Drink>(){
@Override
public int compare(Drink d1, Drink d2){
// Edit this method as you need
return d1.getA().compareTo(d2.getA());
}
});
}
}
class类main类{
列出饮料清单；
公共静态void main（字符串[]args）{
饮料=新的ArrayList（）；
饮料。添加（新饮料（15,1，“D1”，“葡萄酒”，1,0））；
饮料。添加（新饮料（15,3，“D3”，“自来水”，2,2））；
//等等。。。
//您可以使用.get（index）检索元素，然后使用其上的getter检索信息
System.out.println（drinks.get（0.getDrinkName（））；
Collections.sort（饮料、新比较器（）{
@凌驾
公共整数比较（饮料d1、饮料d2）{
//根据需要编辑此方法
返回d1.getA（）.compareTo（d2.getA（））；
}
});
}
}
class Drink{
private int a;
private int b;
private String c;
private String drinkName;
private int d;
private int e;
public Drink(int a,int b,String c,String drinkName,int d,int e){
this.a=a;
this.b=b;
this.c=c;
this.drinkName=drinkName;
this.d=d;
this.e=e;
}
// Getters and setters here
public String getDrinkName(){
return drinkName;
}
// .....
}
class MainClass{
List<Drink> drinks;
public static void main(String[] args){
drinks = new ArrayList<>();
drinks.add(new Drink(15,1,"D1","Wine",1,0));
drinks.add(new Drink(15,3,"D3","Tap Water",2,2));
// Etc...
// You can retrieve elements using .get(index) and then use getters on it to retrieve informations
System.out.println(drinks.get(0).getDrinkName());
Collections.sort(drinks,new Comparator<Drink>(){
@Override
public int compare(Drink d1, Drink d2){
// Edit this method as you need
return d1.getA().compareTo(d2.getA());
}
});
}
}
class类main类{
列出饮料清单；
公共静态void main（字符串[]args）{
饮料=新的ArrayList（）；
饮料。添加（新饮料（15,1，“D1”，“葡萄酒”，1,0））；
饮料。添加（新饮料（15,3，“D3”，“自来水”，2,2））；
//等等。。。
//您可以使用.get（index）检索元素，然后使用其上的getter检索信息
System.out.println（drinks.get（0.getDrinkName（））；
Collections.sort（饮料、新比较器（）{
@凌驾
公共整数比较（饮料d1、饮料d2）{
//根据需要编辑此方法
返回d1.getA（）.compareTo（d2.getA（））；
}
});
}
}
字符串数组MyCustomDataMyCustomDataMyCustomDatapublic class MyCustomData {
private int value1;//holds your element to be sorted
//other values //define other values to hold fish, etc..
public int getValue1() {
return value1;
}
public void setValue1(int value1) {
this.value1 = value1;
}
}
public static void main(String[] args) {
MyCustomData[] myCustomDataArray = new MyCustomData[5];
MyCustomData myCustomData1 = new MyCustomData();
myCustomData1.setValue1(1);
myCustomDataArray[0] = myCustomData1;
//Create and Load other objects myCustomDataArray[1] , [2], ....into array
Comparator<MyCustomData> comp = (MyCustomData data1, MyCustomData data2)
-> data1.getValue1()-data2.getValue1();
Arrays.stream(myCustomDataArray).sorted(comp);
}
public class MyCustomData {
private int value1;//holds your element to be sorted
//other values //define other values to hold fish, etc..
public int getValue1() {
return value1;
}
public void setValue1(int value1) {
this.value1 = value1;
}
}
public static void main(String[] args) {
MyCustomData[] myCustomDataArray = new MyCustomData[5];
MyCustomData myCustomData1 = new MyCustomData();
myCustomData1.setValue1(1);
myCustomDataArray[0] = myCustomData1;
//Create and Load other objects myCustomDataArray[1] , [2], ....into array
Comparator<MyCustomData> comp = (MyCustomData data1, MyCustomData data2)
-> data1.getValue1()-data2.getValue1();
Arrays.stream(myCustomDataArray).sorted(comp);
}
publicstaticvoidmain（字符串[]args）{
MyCustomData[]myCustomDataArray=新的MyCustomData[5]；
MyCustomData myCustomData1=新的MyCustomData（）；
myCustomData1.setValue1（1）；
myCustomDataArray[0]=myCustomData1；
//创建其他对象myCustomDataArray[1]、[2]、…并将其加载到数组中
比较器comp=（MyCustomData数据1，MyCustomData数据2）
->data1.getValue1（）-data2.getValue1（）；
流（myCustomDataArray）.sorted（comp）；
}
字符串数组MyCustomDataMyCustomDataMyCustomDatapublic class MyCustomData {
private int value1;//holds your element to be sorted
//other values //define other values to hold fish, etc..
public int getValue1() {
return value1;
}
public void setValue1(int value1) {
this.value1 = value1;
}
}
public static void main(String[] args) {
MyCustomData[] myCustomDataArray = new MyCustomData[5];
MyCustomData myCustomData1 = new MyCustomData();
myCustomData1.setValue1(1);
myCustomDataArray[0] = myCustomData1;
//Create and Load other objects myCustomDataArray[1] , [2], ....into array
Comparator<MyCustomData> comp = (MyCustomData data1, MyCustomData data2)
-> data1.getValue1()-data2.getValue1();
Arrays.stream(myCustomDataArray).sorted(comp);
}
public class MyCustomData {
private int value1;//holds your element to be sorted
//other values //define other values to hold fish, etc..
public int getValue1() {
return value1;
}
public void setValue1(int value1) {
this.value1 = value1;
}
}
public static void main(String[] args) {
MyCustomData[] myCustomDataArray = new MyCustomData[5];
MyCustomData myCustomData1 = new MyCustomData();
myCustomData1.setValue1(1);
myCustomDataArray[0] = myCustomData1;
//Create and Load other objects myCustomDataArray[1] , [2], ....into array
Comparator<MyCustomData> comp = (MyCustomData data1, MyCustomData data2)
-> data1.getValue1()-data2.getValue1();
Arrays.stream(myCustomDataArray).sorted(comp);
}
publicstaticvoidmain（字符串[]args）{
MyCustomData[]myCustomDataArray=新的MyCustomData[5]；
MyCustomData myCustomData1=新的MyCustomData（）；
myCustomData1.setValue1（1）；
myCustomDataArray[0]=myCustomData1；
//创建其他对象myCustomDataArray[1]、[2]、…并将其加载到数组中
比较器comp=（MyCustomData数据1，MyCustomData数据2）
->data1.getValue1（）-data2.getValue1（）；
流（myCustomDataArray）.sorted（comp）；
}
public static void main(String[] args) {
String[] array1 =
{"15", "1", "D1", "Wine", "1", "0",
"15", "3", "D3", "Tap water", "2", "2",
"15", "1", "M1", "Fish", "3", "0",
"9", "5", "D4", "Coffee", "2", "2",
"9", "2", "P2", "Cake", "2", "1"
};
Comparator<String[]> comparator = new Comparator<String[]>(){
@Override
public int compare(String[]a1, String[] a2) {
return Integer.valueOf(a1[1]).compareTo(Integer.valueOf(a2[1]));
}
};
int lineLength=6;
bubbleSort(array1,lineLength,comparator);
System.out.println(Arrays.toString(array1));
}
//classic bubble-sort algorithm
public static void bubbleSort(String[]array1,int lineLength,Comparator<String[]> comparator){
int numRow=array1.length/lineLength;
for(int i=0;i<numRow;i++){
for(int j=i+1;j<numRow;j++){
String[] extractArrayI = extractArray(array1, i, lineLength);
String[] extractArrayJ = extractArray(array1, j, lineLength);
if(comparator.compare(extractArrayI, extractArrayJ)>0){
swichLines(array1,i,j,lineLength);
}
}
}
}
//extract i-th row
public static String[] extractArray(String[]array,int i, int lineLength){
String [] a= new String[lineLength];
System.arraycopy(array, i*lineLength, a, 0, lineLength);
return a;
}
//Switch line i,j
public static void swichLines(String[]array,int i, int j,int lineLength){
String [] temp = new String[lineLength];
System.arraycopy(array, i*lineLength, temp, 0, lineLength);
System.arraycopy(array, j*lineLength, array, i*lineLength, lineLength);
System.arraycopy(temp, 0, array, j*lineLength, lineLength);
}
如果您创建了一些有用的方法和比较器，您可以使用经典的排序方法，如冒泡排序：
public static void main(String[] args) {
String[] array1 =
{"15", "1", "D1", "Wine", "1", "0",
"15", "3", "D3", "Tap water", "2", "2",
"15", "1", "M1", "Fish", "3", "0",
"9", "5", "D4", "Coffee", "2", "2",
"9", "2", "P2", "Cake", "2", "1"
};
Comparator<String[]> comparator = new Comparator<String[]>(){
@Override
public int compare(String[]a1, String[] a2) {
return Integer.valueOf(a1[1]).compareTo(Integer.valueOf(a2[1]));
}
};
int lineLength=6;
bubbleSort(array1,lineLength,comparator);
System.out.println(Arrays.toString(array1));
}
//classic bubble-sort algorithm
public static void bubbleSort(String[]array1,int lineLength,Comparator<String[]> comparator){
int numRow=array1.length/lineLength;
for(int i=0;i<numRow;i++){
for(int j=i+1;j<numRow;j++){
String[] extractArrayI = extractArray(array1, i, lineLength);
String[] extractArrayJ = extractArray(array1, j, lineLength);
if(comparator.compare(extractArrayI, extractArrayJ)>0){
swichLines(array1,i,j,lineLength);
}
}
}
}
//extract i-th row
public static String[] extractArray(String[]array,int i, int lineLength){
String [] a= new String[lineLength];
System.arraycopy(array, i*lineLength, a, 0, lineLength);
return a;
}
//Switch line i,j
public static void swichLines(String[]array,int i, int j,int lineLength){
String [] temp = new String[lineLength];
System.arraycopy(array, i*lineLength, temp, 0, lineLength);
System.arraycopy(array, j*lineLength, array, i*lineLength, lineLength);
System.arraycopy(temp, 0, array, j*lineLength, lineLength);
}
你好到目前为止你试过什么？你能提出这个问题吗？看起来你使用了错误的数据结构你的“行”在你的数据结构中没有这样标记-首先将它转换成一个行数组（带有一些“行”类型，例如数组），这会让事情变得更简单。然后，您只需要实现一个比较器，就可以使用标准的排序函数。完成了，不使用其他类（我使用的是primitive array，而不是ArrayList）嗨！到目前为止你试过什么？你能提出这个问题吗？看起来你使用了错误的数据结构你的“行”在你的数据结构中没有这样标记-首先将它转换成一个行数组（带有一些“行”类型，例如数组），这会让事情变得更简单。然后，您只需要实现一个比较器，就可以使用标准的排序函数。完成它，而不使用其他类（我使用prim