我尝试使用插入排序来对球员的击球率进行排序。我得到一条错误消息＆＃34; java.util.ArrayList类型中的get（int）方法不适用于参数（double）＆＃34;在S.get（外部）和S.get（内部 - 1）
的行上我做错了什么？ 我该如何解决这个问题？
import java.util.*;
import java.io.*;
class menu {
public static void main (String [] arg) throws IOException
{
PlayerRip.PlayerInfo obj5 = new PlayerRip.PlayerInfo();
ArrayList<Player> obj6 = new ArrayList<Player>();
MainMenu(obj5, obj6);
}
public static void MainMenu(PlayerRip P, ArrayList<Player> S) throws IOException
{
Scanner keyboard = new Scanner(System.in);
int response = 0;
int response2 = 0;
ArrayList<Player> obj1 = new ArrayList<Player>();
obj1.add(new Player("Agostini", "Aldo", "Pitcher", 170, 20, 72, 12, 6, 1, 1, 0));
do
{
System.out.println("1. Open A file:");
System.out.println("7. Exit the program");
response = keyboard.nextInt();
switch (response)
{
case 1:
{
openFile(obj1);
do
{
System.out.println("2. Display all players");
System.out.println("3. Enter player's Height");
System.out.println("4. Sort all players alphabetically by Surname");
System.out.println("5. Sort all players by batting average");
System.out.println("6. Delete a player by selecting the player's surname from a list");
System.out.println("7. Add a player to the stats");
System.out.println("8. Save stats to a file");
System.out.println("9. Exit the program");
response2 = keyboard.nextInt();
switch (response2)
{
case 2:
{
displayInfo(obj1);
break;
}
case 3:
{
changeHeight(obj1);
break;
}
case 4:
{
BubbleSort(obj1);
break;
}
case 5:
{
break;
}
case 6:
{
deletePlayerInfo(obj1);
break;
}
case 7:
{
addPlayerInfo(obj1);
break;
}
case 8:
{
saveFile(obj1);
break;
}
case 9:
{
System.exit(0);
break;
}
}
} while (response2 != 9);
break;
}
case 7:
{
System.exit(0);
break;
}
}
} while (response != 1 || response != 7); // End of switch statement
}
public static void displayInfo(ArrayList<Player> S) {
System.out.printf("%10s %10s %10s \t %4s %4s \t %4s \t %4s %4s \t %4s %4s %4s \n", "Surname", "GivenName", "Postition", "Height(cm)", "Hits", "AtBats", "Singles", "Doubles", "Triples", "HomeRuns", "Batting Average");
for (int index = 0; index < S.size(); index++)
S.get(index).displayInfo();
}
public static void openFile(ArrayList<Player> S) throws IOException // This method allows the oepning of files into the program
{
Scanner userInput = new Scanner(System.in);
String fileName;
S.removeAll(S); // Empties the list readies it for a new oned
System.out.println("Enter a file name to open: ");
fileName = userInput.next().trim();
File file = new File(fileName);
if (file.exists()) // Checks whether or not the file exists in the directory
{
Scanner fileInput = new Scanner(file);
while (fileInput.hasNext())
{
S.add(new Player(fileInput.next(), fileInput.next(), fileInput.next(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextInt(), fileInput.nextDouble())); // If it exists it adds the token values into the respective lists
}
fileInput.close(); // Closes further file input
}
else // Error message incase the file-name is not valid
System.out.println("FILE NOT FOUND");
}
public static void saveFile(ArrayList<Player> S) throws IOException // This method allows for the saving of values to an external file
{
Scanner inputInfo = new Scanner(System.in);
String fileName;
System.out.println("Enter a file name to save the info with:");
fileName = inputInfo.next().trim();
File file = new File(fileName);
PrintStream writeFile = new PrintStream(file);
for (int i = 0; i < S.size(); i++) // Gathers all values and prints them to the file in their respective format
{
writeFile.print(S.get(i).getName() + " ");
writeFile.print(S.get(i).getName2() + " ");
writeFile.print(S.get(i).getPosition() + " ");
for (int j = 0; j < 7; j++)
writeFile.print(S.get(i).getMark(j) + " ");
for (int j = 0; j < 1; j++)
writeFile.print(S.get(i).getBatAvg(j));
writeFile.println(" ");
}
writeFile.close(); // Stops any further writing to the file
}
public static void deletePlayerInfo(ArrayList<Player> S) // THis method allows the user to delete any player within the list
{
int deleteIt = 0;
Scanner keyboard = new Scanner(System.in);
System.out.println("Please select the number of the player to be deleted: ");
for (int i = 0; i < S.size(); i++) // Displays only the first/surNames of the players
{
System.out.print(i + ". " + S.get(i).getName());
System.out.println(" ");
}
deleteIt = keyboard.nextInt();
S.remove(deleteIt);
}
public static void addPlayerInfo(ArrayList<Player> S) // This method allows the user to add a new player to the list
{
String firstName = "";
String surName = "";
String posName = "";
int heightVal = 0;
int hitsVal = 0;
int atBatsVal = 0;
int singVal = 0;
int doubVal = 0;
int tripVal = 0;
int homeVal = 0;
Scanner keyboard = new Scanner(System.in); // Various user input
System.out.println("Enter the surname and name of the new player: ");
System.out.println("Surname: ");
surName = keyboard.nextLine();
System.out.println("Name: ");
firstName = keyboard.nextLine();
System.out.println("Enter the position of the new player: ");
System.out.println("Position: ");
posName = keyboard.nextLine();
System.out.println("Enter the height of the new player: ");
heightVal = keyboard.nextInt();
System.out.println("Enter the batting statistics: ");
System.out.println("Hits: ");
hitsVal = keyboard.nextInt();
System.out.println("AtBats: ");
atBatsVal = keyboard.nextInt();
System.out.println("Singles: ");
singVal = keyboard.nextInt();
System.out.println("Doubles: ");
doubVal = keyboard.nextInt();
System.out.println("Triples: ");
tripVal = keyboard.nextInt();
System.out.println("HomeRuns: ");
homeVal = keyboard.nextInt();
S.add(new Player(surName, firstName, posName, heightVal, hitsVal, atBatsVal, singVal, doubVal, tripVal, homeVal, 0));
}
public static void changeHeight(ArrayList<Player> S)
{
int playerSel = 0;
int newHeight = 0;
Scanner keyboard = new Scanner(System.in); // Various user input
System.out.println("Select a player to enter the height for: ");
do
{
for (int i = 0; i < S.size(); i++) // Displays only the first/surNames of the players
{
System.out.print(i + ". " + S.get(i).getName());
System.out.println(" ");
}
playerSel = keyboard.nextInt();
System.out.println("Enter the height for this character: ");
newHeight = keyboard.nextInt();
if (newHeight < 125 && newHeight > 240)
{
System.out.println("WRONG! TRY AGAIN!");
}
else
{
}
} while (newHeight >= 125 && newHeight <= 240);
}
public static void BubbleSort(ArrayList<Player> S){
Player strTemp;
int i = 0;
boolean isSorted = false;
while(i < S.size()&&isSorted==false)
{
isSorted = true;
for(int j = 0; j < (S.size()-1)-i;j++)
{
if(S.get(j).getName().compareToIgnoreCase(S.get(j+1).getName())>0){
strTemp = S.get(j);
S.set(j,S.get(j+1));
S.set(j+1,strTemp);
isSorted = false;
}
}
i++;}
}
public static void InsertionSort(ArrayList<Player> S){ // hits over atbats
int outer;
double inner;
for(outer = 1; outer < S.size();outer++){
double keyItem = S.get(outer).getBatAvg();
inner = outer - 1 ;
while(inner >0&&S.get(inner-1).getBatAvg() > keyItem){
S.set((inner),S.get(inner-1));
inner--;
break;
}
double helpSort = S.get(inner).getBatAvg();
helpSort = keyItem;
}
}
}
class PlayerRip {
public String name;
public String name2;
public String position;
public int [ ] mark = new int[7];
public double [ ] batAvg = new double[1];
static class PlayerInfo extends PlayerRip
{
PlayerInfo() {
this.name = "-1";
this.name2 = "-1";
this.position = "-1";
for (int i=0; i < mark.length; i++)
mark[i] = -1;
}
PlayerInfo(String nam, String nam2, String pos, int a, int b, int c, int d, int e, int f, int g, double h) {
this.name = nam;
this.name2 = nam2;
this.position = pos;
this.mark[0] = a; this.mark[1] = b; this.mark[2] = c; this.mark[3] = d; this.mark[4] = e; this.mark[5] = f; this.mark[6] = g;
batAvg[0] = (((double)mark[1] / (double)mark[2]) * 100);
}
public void setName(String nam) { name = nam; }
public void setName2(String nam2) { name2 = nam2; }
public void setPosition(String pos) { position = pos; }
public void setMark(int index, int mark) { this.mark[index] = mark; }
public void setBatAvg(int index, double batAvg) {this.batAvg[index] = batAvg;}
public String getName() { return this.name; }
public String getName2() { return this.name2; }
public String getPosition() { return this.position; }
public double getBatAvg() { return this.batAvg[0];}
public int getMark(int index) { return this.mark[index]; }
public void setHeight(int index, int mark) { this.mark[index] = mark; }
public int getHeight(int index) { return this.mark[0]; }
public void setHits (int index, int mark) { this.mark [index] = mark; }
public int getHits (int index) { return this.mark [1]; }
public void setAtBats (int index, int mark) { this.mark [index] = mark; }
public int getAtBats(int index) { return this.mark [2]; }
public void setSingles (int index, int mark) { this.mark [index] = mark; }
public int getSingles (int index) { return this.mark [3] ; }
public void setDoubles (int index, int mark) { this.mark [index] = mark; }
public int getDoubles (int index) { return this.mark [4] ; }
public void setTriples (int index, int mark) { this.mark [index] = mark; }
public int getTriples (int index) { return this.mark [5] ; }
public void setHomeRuns (int index, int mark) { this.mark [index] = mark; }
public int getHomeRuns (int index) { return this.mark [6] ; }
}
}
对不起格式新网站
}
public static void InsertionSort(ArrayList<Player> S){ // hits over atbats
int outer;
double inner;
for(outer = 1; outer < S.size();outer++){
double keyItem = S.get(outer).getBatAvg();
inner = outer - 1 ;
while(inner >0&&S.get(inner-1).getBatAvg() > keyItem){
S.set((inner),S.get(inner-1));
inner--;
break;
}
double helpSort = S.get(inner).getBatAvg();
helpSort = keyItem;
}
}
}
是问题的具体领域
答案 0 :(得分：0)
S.get()和S.set()接受一个int变量，以便将内部转换为int。
答案 1 :(得分：0)
您将inner定义为double，在Java中，当您使用double和int（例如inner - 1）进行数学运算时，结果你得到double。 This page有一个相当不错的解释。
然后，当您说S.get(inner - 1)时，您说要使用double作为ArrayList中的索引。 documentation for ArrayList.get表示您只能使用int作为索引，这就是您收到编译错误的原因。您还只允许使用int作为set的索引，这就是编译器会抱怨S.set(inner, ...)的原因。
您可以将inner投射到int，但最好先将其声明为int，因为它没有理由需要成为double。