当我 运行 jar 文件时，我无法正确读取文件
When i run jar file i can't read files correctly
我写了一个代码，通过读取csv文件中的信息，根据那些城市的区域创建城市和区域。 csv 文件长 81 行。它包含来自土耳其 81 个城市的一些信息。我想将此 csv 文件中的每一行添加到一个字符串数组中，然后将其打印在屏幕上。我还想将使用此信息创建的区域对象保存在区域数组中。然后，我想从这个区域数组中打印区域名称。土耳其有7个地区。
编辑：我尝试从 txt 文件而不是 csv 文件中读取数据。我再次遇到同样的错误。另外，我正在尝试 运行 jar on Windows。我在 windows(10) 上遇到这些错误，但是当我尝试 运行 ubuntu 上的程序时，我没有。
该代码在 Eclipse 上看起来运行良好，它提供了我想要的输出。
output
我想 运行 这个程序和可执行 jar file.So，我通过 Eclipse 将项目导出为 运行nable jar，但是当我尝试 运行在 cmd 上输入这个 jar 文件：
java -jar myjar.jar
我收到这样的错误。
error
我不知道为什么会出现此错误。 CSV文件如下
CSV
当我运行用eclipse一步一步的程序时，我找不到任何可能导致错误的地方。你怎么看待这个问题？
我哪里会出错？
这是我所有的 class 定义。
主要class
import java.io.FileNotFoundException;
public class Launcher {
public static void main(String[] args) throws FileNotFoundException {
String[] infoArray = ArrayCreator.createInfoArray("Cities.csv");
for (String info : infoArray) {
System.out.println(info);
}
System.out.println();
Region[] regionArray = ArrayCreator.createRegionArray(infoArray);
for (Region region : regionArray) {
System.out.println(region.getName());
}
}
}
数组创建者class
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class ArrayCreator {
private static int capacityDetector(String fileName) throws FileNotFoundException {
Scanner scanner1 = new Scanner(new File(fileName));
int count = 0;
while (scanner1.hasNext()) {
count++;
scanner1.nextLine();
}
scanner1.close();
return count;
}
public static String[] createInfoArray(String fileName) throws FileNotFoundException {
int capacity = capacityDetector(fileName);
Scanner scanner2 = new Scanner(new File(fileName));
String[] returnArray = new String[capacity];
int index = 0;
while (scanner2.hasNextLine()) {
returnArray[index] = scanner2.nextLine();
index++;
}
scanner2.close();
return returnArray;
}
/**
* This method creates an array which contains all the region.
*
* @param infoArray String array about the cities and their regions information.
* Elements must be in the CSV format and should be compatible
* with other parts of the project.
* @return an array which contains all the regions.
*/
public static Region[] createRegionArray(String[] infoArray) {
// infoArray is actually city information array. So there may be too many
// times for the same region information. We just want to create only one region
// for the same regions. So, we must do not create the regions that are already
// exist.
int index = 0;
Region[] regionArr = new Region[index + 1];
regionArr[index] = new Region(infoArray[0]); // We are sure that the region in the first information was not
// created before.
for (int i = 1; i < infoArray.length; i++) {
String info = infoArray[i];
String[] splitted_info = info.split(",");
boolean found = false;
for (Region region : regionArr) {
String newRegionName = splitted_info[3];
String currRegionName = region.getName();
if (newRegionName.equals(currRegionName)) {
found = true;
break;
}
}
if (!found) { // if the object of this region was not created before.
index++;
Region new_region = new Region(info); // We dont know how many regions are there and we work with
// arrays. So we have to increase the array size manually.
Region[] temp = new Region[index + 1];
for (int j = 0; j < regionArr.length; j++) {
temp[j] = regionArr[j];
}
temp[index] = new_region;
regionArr = temp;
}
}
return regionArr;
}
}
地区class
public class Region {
private int ID;
private String name;
private City[] cities;
/**
* Constructor for Region Class Object.
*
* @param name Name of the region.
*/
public Region(String info) {
String[] splitted_info = info.split(",");
this.ID = Integer.parseInt(splitted_info[2]);
this.name = splitted_info[3];
}
/**
* A helper method to find the number of the cities which are in this region.
*
* @param allCities An array which contains all the cities.
* @return An integer which is the number of the cities in this region.
*
*/
private int findCitiesOfRegionArraySize(City[] allCities) {
int returnInt = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName().equals(this.name)) {
returnInt++;
}
}
return returnInt;
}
/**
* Creates the City array of a region.
*
* @param allCities An array which contains all the cities.
* @return City array that contains all the cities in this region.
*/
public void createCitiesOfRegion(City[] allCities) {
City[] cityArray = new City[findCitiesOfRegionArraySize(allCities)];
int index = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName() == this.name) {
cityArray[index] = aCity;
index++;
}
}
this.cities = cityArray;
}
public int getID() {
return ID;
}
public String getName() {
return name;
}
public City[] getCities() {
return cities;
}
}
城市class
public class Region {
private int ID;
private String name;
private City[] cities;
/**
* Constructor for Region Class Object.
*
* @param name Name of the region.
*/
public Region(String info) {
String[] splitted_info = info.split(",");
this.ID = Integer.parseInt(splitted_info[2]);
this.name = splitted_info[3];
}
/**
* A helper method to find the number of the cities which are in this region.
*
* @param allCities An array which contains all the cities.
* @return An integer which is the number of the cities in this region.
*
*/
private int findCitiesOfRegionArraySize(City[] allCities) {
int returnInt = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName().equals(this.name)) {
returnInt++;
}
}
return returnInt;
}
/**
* Creates the City array of a region.
*
* @param allCities An array which contains all the cities.
* @return City array that contains all the cities in this region.
*/
public void createCitiesOfRegion(City[] allCities) {
City[] cityArray = new City[findCitiesOfRegionArraySize(allCities)];
int index = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName() == this.name) {
cityArray[index] = aCity;
index++;
}
}
this.cities = cityArray;
}
public int getID() {
return ID;
}
public String getName() {
return name;
}
public City[] getCities() {
return cities;
}
}
当我使用 BufferedReader 从 CSV 文件中读取数据而不是使用 Scanner 读取数据时，我的问题得到了解决。此外，我将必要的文件（csv 文件）作为嵌入资源，将它们放入名为资源的包中。
我用这个来检测容量
private static int capacityDetector(String filename) throws IOException {
InputStream in = new FileIO().getClass().getResourceAsStream(filename);
@SuppressWarnings("resource")
BufferedReader csv = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
int capacity = 0;
@SuppressWarnings("unused")
String line;
while ((line = csv.readLine()) != null) {
capacity++;
}
return capacity;
}
而不是
private static int capacityDetector(String fileName) throws FileNotFoundException {
Scanner scanner1 = new Scanner(new File(fileName));
int count = 0;
while (scanner1.hasNext()) {
count++;
scanner1.nextLine();
}
scanner1.close();
return count;
}
我用这段代码创建了信息数组
public static String[] createInfoArray(String filename) throws IOException {
InputStream in = new FileIO().getClass().getResourceAsStream(filename);
@SuppressWarnings("resource")
BufferedReader csv = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
int capacity = capacityDetector(filename);
String[] infoArray = new String[capacity];
for (int i = 0; i < capacity; i++) {
infoArray[i] = csv.readLine();
}
return infoArray;
}
而不是
public static String[] createInfoArray(String fileName) throws FileNotFoundException {
int capacity = capacityDetector(fileName);
Scanner scanner2 = new Scanner(new File(fileName));
String[] returnArray = new String[capacity];
int index = 0;
while (scanner2.hasNextLine()) {
returnArray[index] = scanner2.nextLine();
index++;
}
scanner2.close();
return returnArray;
}
最后，我在main like中调用了这些方法
String[] cityInfoArray = FileIO.createInfoArray("/resources/Cities.csv");
String[] forecastInfoArray = FileIO.createInfoArray("/resources/WeeklyForecast.csv");
现在，我可以通过双击 jar 文件 运行 我的程序而不会出现任何问题。
我写了一个代码，通过读取csv文件中的信息，根据那些城市的区域创建城市和区域。 csv 文件长 81 行。它包含来自土耳其 81 个城市的一些信息。我想将此 csv 文件中的每一行添加到一个字符串数组中，然后将其打印在屏幕上。我还想将使用此信息创建的区域对象保存在区域数组中。然后，我想从这个区域数组中打印区域名称。土耳其有7个地区。
编辑：我尝试从 txt 文件而不是 csv 文件中读取数据。我再次遇到同样的错误。另外，我正在尝试 运行 jar on Windows。我在 windows(10) 上遇到这些错误，但是当我尝试 运行 ubuntu 上的程序时，我没有。
该代码在 Eclipse 上看起来运行良好，它提供了我想要的输出。
output
我想 运行 这个程序和可执行 jar file.So，我通过 Eclipse 将项目导出为 运行nable jar，但是当我尝试 运行在 cmd 上输入这个 jar 文件：
java -jar myjar.jar
我收到这样的错误。
error
我不知道为什么会出现此错误。 CSV文件如下
CSV
当我运行用eclipse一步一步的程序时，我找不到任何可能导致错误的地方。你怎么看待这个问题？
我哪里会出错？
这是我所有的 class 定义。
主要class
import java.io.FileNotFoundException;
public class Launcher {
public static void main(String[] args) throws FileNotFoundException {
String[] infoArray = ArrayCreator.createInfoArray("Cities.csv");
for (String info : infoArray) {
System.out.println(info);
}
System.out.println();
Region[] regionArray = ArrayCreator.createRegionArray(infoArray);
for (Region region : regionArray) {
System.out.println(region.getName());
}
}
}
数组创建者class
import java.io.File;
import java.io.FileNotFoundException;
import java.util.Scanner;
public class ArrayCreator {
private static int capacityDetector(String fileName) throws FileNotFoundException {
Scanner scanner1 = new Scanner(new File(fileName));
int count = 0;
while (scanner1.hasNext()) {
count++;
scanner1.nextLine();
}
scanner1.close();
return count;
}
public static String[] createInfoArray(String fileName) throws FileNotFoundException {
int capacity = capacityDetector(fileName);
Scanner scanner2 = new Scanner(new File(fileName));
String[] returnArray = new String[capacity];
int index = 0;
while (scanner2.hasNextLine()) {
returnArray[index] = scanner2.nextLine();
index++;
}
scanner2.close();
return returnArray;
}
/**
* This method creates an array which contains all the region.
*
* @param infoArray String array about the cities and their regions information.
* Elements must be in the CSV format and should be compatible
* with other parts of the project.
* @return an array which contains all the regions.
*/
public static Region[] createRegionArray(String[] infoArray) {
// infoArray is actually city information array. So there may be too many
// times for the same region information. We just want to create only one region
// for the same regions. So, we must do not create the regions that are already
// exist.
int index = 0;
Region[] regionArr = new Region[index + 1];
regionArr[index] = new Region(infoArray[0]); // We are sure that the region in the first information was not
// created before.
for (int i = 1; i < infoArray.length; i++) {
String info = infoArray[i];
String[] splitted_info = info.split(",");
boolean found = false;
for (Region region : regionArr) {
String newRegionName = splitted_info[3];
String currRegionName = region.getName();
if (newRegionName.equals(currRegionName)) {
found = true;
break;
}
}
if (!found) { // if the object of this region was not created before.
index++;
Region new_region = new Region(info); // We dont know how many regions are there and we work with
// arrays. So we have to increase the array size manually.
Region[] temp = new Region[index + 1];
for (int j = 0; j < regionArr.length; j++) {
temp[j] = regionArr[j];
}
temp[index] = new_region;
regionArr = temp;
}
}
return regionArr;
}
}
地区class
public class Region {
private int ID;
private String name;
private City[] cities;
/**
* Constructor for Region Class Object.
*
* @param name Name of the region.
*/
public Region(String info) {
String[] splitted_info = info.split(",");
this.ID = Integer.parseInt(splitted_info[2]);
this.name = splitted_info[3];
}
/**
* A helper method to find the number of the cities which are in this region.
*
* @param allCities An array which contains all the cities.
* @return An integer which is the number of the cities in this region.
*
*/
private int findCitiesOfRegionArraySize(City[] allCities) {
int returnInt = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName().equals(this.name)) {
returnInt++;
}
}
return returnInt;
}
/**
* Creates the City array of a region.
*
* @param allCities An array which contains all the cities.
* @return City array that contains all the cities in this region.
*/
public void createCitiesOfRegion(City[] allCities) {
City[] cityArray = new City[findCitiesOfRegionArraySize(allCities)];
int index = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName() == this.name) {
cityArray[index] = aCity;
index++;
}
}
this.cities = cityArray;
}
public int getID() {
return ID;
}
public String getName() {
return name;
}
public City[] getCities() {
return cities;
}
}
城市class
public class Region {
private int ID;
private String name;
private City[] cities;
/**
* Constructor for Region Class Object.
*
* @param name Name of the region.
*/
public Region(String info) {
String[] splitted_info = info.split(",");
this.ID = Integer.parseInt(splitted_info[2]);
this.name = splitted_info[3];
}
/**
* A helper method to find the number of the cities which are in this region.
*
* @param allCities An array which contains all the cities.
* @return An integer which is the number of the cities in this region.
*
*/
private int findCitiesOfRegionArraySize(City[] allCities) {
int returnInt = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName().equals(this.name)) {
returnInt++;
}
}
return returnInt;
}
/**
* Creates the City array of a region.
*
* @param allCities An array which contains all the cities.
* @return City array that contains all the cities in this region.
*/
public void createCitiesOfRegion(City[] allCities) {
City[] cityArray = new City[findCitiesOfRegionArraySize(allCities)];
int index = 0;
for (City aCity : allCities) {
if (aCity.getRegion().getName() == this.name) {
cityArray[index] = aCity;
index++;
}
}
this.cities = cityArray;
}
public int getID() {
return ID;
}
public String getName() {
return name;
}
public City[] getCities() {
return cities;
}
}
当我使用 BufferedReader 从 CSV 文件中读取数据而不是使用 Scanner 读取数据时，我的问题得到了解决。此外，我将必要的文件（csv 文件）作为嵌入资源，将它们放入名为资源的包中。
我用这个来检测容量
private static int capacityDetector(String filename) throws IOException {
InputStream in = new FileIO().getClass().getResourceAsStream(filename);
@SuppressWarnings("resource")
BufferedReader csv = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
int capacity = 0;
@SuppressWarnings("unused")
String line;
while ((line = csv.readLine()) != null) {
capacity++;
}
return capacity;
}
而不是
private static int capacityDetector(String fileName) throws FileNotFoundException {
Scanner scanner1 = new Scanner(new File(fileName));
int count = 0;
while (scanner1.hasNext()) {
count++;
scanner1.nextLine();
}
scanner1.close();
return count;
}
我用这段代码创建了信息数组
public static String[] createInfoArray(String filename) throws IOException {
InputStream in = new FileIO().getClass().getResourceAsStream(filename);
@SuppressWarnings("resource")
BufferedReader csv = new BufferedReader(new InputStreamReader(in, StandardCharsets.UTF_8));
int capacity = capacityDetector(filename);
String[] infoArray = new String[capacity];
for (int i = 0; i < capacity; i++) {
infoArray[i] = csv.readLine();
}
return infoArray;
}
而不是
public static String[] createInfoArray(String fileName) throws FileNotFoundException {
int capacity = capacityDetector(fileName);
Scanner scanner2 = new Scanner(new File(fileName));
String[] returnArray = new String[capacity];
int index = 0;
while (scanner2.hasNextLine()) {
returnArray[index] = scanner2.nextLine();
index++;
}
scanner2.close();
return returnArray;
}
最后，我在main like中调用了这些方法
String[] cityInfoArray = FileIO.createInfoArray("/resources/Cities.csv");
String[] forecastInfoArray = FileIO.createInfoArray("/resources/WeeklyForecast.csv");
现在，我可以通过双击 jar 文件 运行 我的程序而不会出现任何问题。