package com.core.common;
import java.io.BufferedReader;
import java.io.FileInputStream;
import java.io.InputStreamReader;
import java.util.ArrayList;
public class CSVFileUtil {
public static void main(String[] arge) {
try {
CSVFileUtil c = new CSVFileUtil("F:\\TI_RECALLED_ACTIVITY.csv", "GBK");
int row = 1;
while (true) {
String line = c.readLine();
if (line == null) {
break;
}
@SuppressWarnings("rawtypes")
ArrayList lineArray = c.fromCSVLinetoArray(line);
if (lineArray != null) {
for (int i = 0; i < lineArray.size(); i++) {
String item = (String) lineArray.get(i);
System.out.println("item[" + row + "][" + i + "]=" + item);
}
}
row++;
}
} catch (Exception e) {
e.printStackTrace();
}
}
private FileInputStream fis = null;
private InputStreamReader isw = null;
private BufferedReader br = null;
public CSVFileUtil(String filename, String encode) throws Exception {
fis = new FileInputStream(filename);
isw = new InputStreamReader(fis, encode);
br = new BufferedReader(isw);
}
// ==========以下是公开方法=============================
/**
* 从CSV文件流中读取一个CSV行。
*
* @throws Exception
*/
public String readLine() throws Exception {
StringBuffer readLine = new StringBuffer();
boolean bReadNext = true;
while (bReadNext) {
//
if (readLine.length() > 0) {
readLine.append("\r\n");
}
// 一行
String strReadLine = br.readLine();
// readLine is Null
if (strReadLine == null) {
return null;
}
readLine.append(strReadLine);
// 如果双引号是奇数的时候继续读取。考虑有换行的是情况。
if (countChar(readLine.toString(), '"', 0) % 2 == 1) {
bReadNext = true;
} else {
bReadNext = false;
}
}
return readLine.toString();
}
/**
* 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。
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
public String[] fromCSVLine(String source, int size) {
ArrayList tmpArray = fromCSVLinetoArray(source);
if (size < tmpArray.size()) {
size = tmpArray.size();
}
String[] rtnArray = new String[size];
tmpArray.toArray(rtnArray);
return rtnArray;
}
/**
* 把CSV文件的一行转换成字符串数组。不指定数组长度。
*/
@SuppressWarnings({ "rawtypes", "unchecked" })
public ArrayList fromCSVLinetoArray(String source) {
if (source == null || source.length() == 0) {
return new ArrayList();
}
int currentPosition = 0;
int maxPosition = source.length();
int nextComma = 0;
ArrayList rtnArray = new ArrayList();
while (currentPosition < maxPosition) {
nextComma = nextComma(source, currentPosition);
rtnArray.add(nextToken(source, currentPosition, nextComma));
currentPosition = nextComma + 1;
if (currentPosition == maxPosition) {
rtnArray.add("");
}
}
return rtnArray;
}
/**
* 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）
*/
public String toCSVLine(String[] strArray) {
if (strArray == null) {
return "";
}
StringBuffer cvsLine = new StringBuffer();
for (int idx = 0; idx < strArray.length; idx++) {
String item = addQuote(strArray[idx]);
cvsLine.append(item);
if (strArray.length - 1 != idx) {
cvsLine.append(',');
}
}
return cvsLine.toString();
}
/**
* 字符串类型的List转换成一个CSV行。（输出CSV文件的时候用）
*/
@SuppressWarnings("rawtypes")
public 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);
}
// ==========以下是内部使用的方法=============================
/**
* 计算指定文字的个数。
*
* @param str 文字列
* @param c 文字
* @param start 开始位置
* @return 个数
*/
private int countChar(String str, char c, int start) {
int i = 0;
int index = str.indexOf(c, start);
return index == -1 ? i : 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 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
*/
private String nextToken(String source, int st, int nextComma) {
StringBuffer strb = new StringBuffer();
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 String addQuote(String item) {
if (item == null || item.length() == 0) {
return "\"\"";
}
StringBuffer sb = new StringBuffer();
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();
}
}