用JAVA读取CSV文件格式，存入List 中，其每个元素为一个String[]

package dong.csv;

import java.io.BufferedReader;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.IOException;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.List;
import java.util.regex.Matcher;
import java.util.regex.Pattern;

public class CSVParser {
	private File file;
	private List<String[]> resultList = new ArrayList<String[]>();
	private static Pattern pattern = Pattern
			.compile(",?\"([^\"]*(\"{2}[^\"]*\"{2}[^\"]*)*)\",?");

	public static void main(String[] args) {
		CSVParser parser = new CSVParser("test.csv");
		List<String[]> list = parser.parse();
		print(list);
	}

	public CSVParser(File file) {
		this.file = file;
	}

	public CSVParser(String filePath) {
		file = new File(filePath);
	}

	private static void print(List<String[]> list) {
		for (int i = 0; i < list.size(); i++)
			System.out.println(Arrays.toString(list.get(i)) + " Length: "
					+ list.get(i).length);
	}

	public List<String[]> parse() {
		try {
			BufferedReader br = getReader();
			String line = "";
			while ((line = br.readLine()) != null) {
				line = handleSpecial(line);
				String[] elements = line.split(",");
				revert(elements);
				store(elements);
			}
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		}
		return resultList;
	}

	/**
	 * Revert to original ',' if contains '|', precondition is that each
	 * original Field of the line doesn't contain this char
	 * 
	 * @param elements
	 */
	private void revert(String[] elements) {
		for (int i = 0; i < elements.length; i++)
			elements[i] = elements[i].replace("|", ",");
	}

	private void store(String[] elements) {
		resultList.add(elements);
	}

	private BufferedReader getReader() {
		BufferedReader br = null;
		try {
			//br = new BufferedReader(new InputStreamReader(new FileInputStream(
				//	file), Charset.forName("GB18030")));// ISO-8859-1,GB18030
			br = new BufferedReader(new FileReader(file));
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		}
		return br;
	}

	/**
	 * Handling special characters for each given line.
	 * 
	 * @param inputLine
	 * @return
	 */
	private String handleSpecial(String inputLine) {
		if (inputLine == null || inputLine.trim().length() == 0)
			return "";
		Matcher m = getMatcher(inputLine);
		String after = "";
		while (m.find()) {
			after = m.group(2);
			String before = after;
			System.out.println("Before: " + before);
			if (after.indexOf(",") > -1)
				// use '|' to replace ',' for later splitting of each field of
				// the line,this '|' needs to be revert to ',' after the whole line being
				// split
				after = after.replace(',', '|');
			if (after.indexOf("\"\"") > -1)
				after = after.replace("\"\"", "\"");
			System.out.println("After:" + after);
			inputLine = inputLine.replace(before, after);
		}

		return inputLine;
	}

	private static Matcher getMatcher(String sequence) {
		return pattern.matcher(sequence);
	}

}

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1 楼 economist 2012-08-16