工具文件，可直接调用，亲测有效：
package com.powersi.biz.park.network.util;
import java.io.*;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
/**
* @Description TODO
* @Author zhouruntao
* @Date 2020/11/11 11:18
*/
public class CsvToListUtil {
/**
* CSV文件编码
*/
private static final String ENCODE = "UTF-8";
/**
* 读取CSV文件得到List，默认使用UTF-8编码
* @param fileName 文件路径
* @return
*/
public static List<String> getLines(String fileName) {
return getLines(fileName, ENCODE);
}
/**
* 读取CSV文件得到List
* @param fileName 文件路径
* @param encode 编码
* @return
*/
public static List<String> getLines(String fileName, String encode) {
List<String> lines = new ArrayList<String>();
BufferedReader br = null;
InputStreamReader isr = null;
FileInputStream fis = null;
try {
fis = new FileInputStream(fileName);
isr = new InputStreamReader(fis, encode);
br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
StringBuilder sb = new StringBuilder();
sb.append(line);
boolean readNext = countChar(sb.toString(), '"', 0) % 2 == 1;
// 如果双引号是奇数的时候继续读取。考虑有换行的是情况
while (readNext) {
line = br.readLine();
if (line == null) {
return null;
}
sb.append(line);
readNext = countChar(sb.toString(), '"', 0) % 2 == 1;
}
lines.add(sb.toString());
}
} catch (Exception e) {
// log.error("Read CSV file failure :{}", e);
System.out.println("Read CSV file failure :{}" + e);
} finally {
try {
if (br != null) {
br.close();
}
if (isr != null) {
isr.close();
}
if (fis != null) {
fis.close();
}
} catch (IOException e) {
// log.error("Close stream failure :{}", e);
System.out.println("Close stream failure :{}" + e);
}
}
return lines;
}
public static List<String> getLines(File file, String encode) {
List<String> lines = new ArrayList<String>();
BufferedReader br = null;
InputStreamReader isr = null;
FileInputStream fis = null;
try {
fis = new FileInputStream(file);
isr = new InputStreamReader(fis, encode);
br = new BufferedReader(isr);
String line;
while ((line = br.readLine()) != null) {
StringBuilder sb = new StringBuilder();
sb.append(line);
boolean readNext = countChar(sb.toString(), '"', 0) % 2 == 1;
// 如果双引号是奇数的时候继续读取。考虑有换行的是情况
while (readNext) {
line = br.readLine();
if (line == null) {
return null;
}
sb.append(line);
readNext = countChar(sb.toString(), '"', 0) % 2 == 1;
}
lines.add(sb.toString());
}
} catch (Exception e) {
// log.error("Read CSV file failure :{}", e);
System.out.println("Read CSV file failure :{}" + e);
} finally {
try {
if (br != null) {
br.close();
}
if (isr != null) {
isr.close();
}
if (fis != null) {
fis.close();
}
} catch (IOException e) {
// log.error("Close stream failure :{}", e);
System.out.println("Close stream failure :{}" + e);
}
}
return lines;
}
public static String[] fromCSVLine(String source) {
return fromCSVLine(source, 0);
}
/**
* 把CSV文件的一行转换成字符串数组。指定数组长度，不够长度的部分设置为null
* @param source
* @param size
* @return
*/
public static String[] fromCSVLine(String source, int size) {
List list = fromCSVLineToArray(source);
if (size < list.size()) {
size = list.size();
}
String[] arr = new String[size];
list.toArray(arr);
return arr;
}
public static List fromCSVLineToArray(String source) {
if (source == null || source.length() == 0) {
return new ArrayList();
}
int currentPosition = 0;
int maxPosition = source.length();
int nextComa = 0;
List list = new ArrayList();
while (currentPosition < maxPosition) {
nextComa = nextComma(source, currentPosition);
list.add(nextToken(source, currentPosition, nextComa));
currentPosition = nextComa + 1;
if (currentPosition == maxPosition) {
list.add("");
}
}
return list;
}
/**
* 把字符串类型的数组转换成一个CSV行。（输出CSV文件的时候用）
*
* @param arr
* @return
*/
public static String toCSVLine(String[] arr) {
if (arr == null) {
return "";
}
StringBuilder sb = new StringBuilder();
for (int i = 0; i < arr.length; i++) {
String item = addQuote(arr[i]);
sb.append(item);
if (arr.length - 1 != i) {
sb.append(",");
}
}
return sb.toString();
}
/**
* 将list的第一行作为Map的key，下面的列作为Map的value
* @param list
* @return
*/
public static List<Map<String, String>> parseList(List<String> list) {
List<Map<String, String>> resultList = new ArrayList<Map<String, String>>();
String firstLine = list.get(0);
String[] fields = firstLine.split(",");
for (int i = 1; i < list.size(); i++) {
String valueLine = list.get(i);
String[] valueItems = CsvToListUtil.fromCSVLine(valueLine);
Map<String, String> map = new HashMap<String, String>();
for (int j = 0; j < fields.length; j++) {
map.put(fields[j], valueItems[j]);
}
resultList.add(map);
}
return resultList;
}
/**
* 字符串类型的List转换成一个CSV行。（输出CSV文件的时候用）
*
* @param strArrList
* @return
*/
public static String toCSVLine(ArrayList strArrList) {
if (strArrList == null) {
return "";
}
String[] strArray = new String[strArrList.size()];
for (int idx = 0; idx < strArrList.size(); idx++) {
strArray[idx] = (String) strArrList.get(idx);
}
return toCSVLine(strArray);
}
/**
* 计算指定字符的个数
*
* @param str 文字列
* @param c 字符
* @param start 开始位置
* @return 个数
*/
private static int countChar(String str, char c, int start) {
int index = str.indexOf(c, start);
return index == -1 ? 0 : countChar(str, c, index + 1) + 1;
}
/**
* 查询下一个逗号的位置。
*
* @param source 文字列
* @param st 检索开始位置
* @return 下一个逗号的位置。
*/
private static int nextComma(String source, int st) {
int maxPosition = source.length();
boolean inquote = false;
while (st < maxPosition) {
char ch = source.charAt(st);
if (!inquote && ch == ',') {
break;
} else if ('"' == ch) {
inquote = !inquote;
}
st++;
}
return st;
}
/**
* 取得下一个字符串
*
* @param source
* @param st
* @param nextComma
* @return
*/
private static String nextToken(String source, int st, int nextComma) {
StringBuilder strb = new StringBuilder();
int next = st;
while (next < nextComma) {
char ch = source.charAt(next++);
if (ch == '"') {
if ((st + 1 < next && next < nextComma) && (source.charAt(next) == '"')) {
strb.append(ch);
next++;
}
} else {
strb.append(ch);
}
}
return strb.toString();
}
/**
* 在字符串的外侧加双引号。如果该字符串的内部有双引号的话，把"转换成""。
*
* @param item 字符串
* @return 处理过的字符串
*/
private static String addQuote(String item) {
if (item == null || item.length() == 0) {
return "\"\"";
}
StringBuilder sb = new StringBuilder();
sb.append('"');
for (int idx = 0; idx < item.length(); idx++) {
char ch = item.charAt(idx);
if ('"' == ch) {
sb.append("\"\"");
} else {
sb.append(ch);
}
}
sb.append('"');
return sb.toString();
}
}
我的调用（我重写了getLines方法，因为我这里要传file文件，而不是传文件路径）：
//调用CSV文件转List工具
List<String> lines = CsvToListUtil.getLines(file, "GBK");
List<Map<String, String>> mapList = CsvToListUtil.parseList(lines);
System.out.println(Arrays.toString(mapList.toArray()));
。。。
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