x-credit-gateway/src/main/java/com/sec/xinhua/gateway/utils/FileHelper.java

package com.sec.xinhua.gateway.utils;

import java.io.File;
import java.io.FileInputStream;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.UnsupportedEncodingException;

import org.apache.log4j.Logger;

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONObject;

public class FileHelper {
    private static final Logger logger = Logger.getLogger(FileHelper.class);

    public static String readFile(final File file) {
        if (file == null) {
            return null;
        }

        String result = null;
        if (file.exists()) {
            InputStream in = null;
            try {
                in = new FileInputStream(file);
                result = readFile(in);
            } catch (Exception e) {
                logger.error("Read file error,the file:" + file.getAbsolutePath(), e);
            } finally {
                if (in != null) {
                    try {
                        in.close();
                    } catch (IOException e) {
                        logger.error("Close stream error,the file:" + file.getAbsolutePath());
                    }
                }
            }
        }

        return result;
    }

    public static String readFile(final InputStream in) throws IOException, UnsupportedEncodingException {
        int len = in.available();
        byte[] data = new byte[len];
        in.read(data, 0, len);
        return new String(data, SysConstants.ENCODE);
    }

    public static void writeFileNotSafe(final String str, final String fileName) throws IOException {
        File file = new File(fileName);
        File fileParent = file.getParentFile();
        if (fileParent != null) {
            fileParent.mkdirs();
        }
        FileWriter fileWriter = null;

        try {
            fileWriter = new FileWriter(file);
            fileWriter.write(str);
        } catch (IOException e) {
            logger.error("Write file error,the file name:" + fileName);
            throw e;
        } finally {
            if (fileWriter != null) {
                try {
                    fileWriter.close();
                } catch (IOException e) {
                    logger.error("Close file writer error,the file name:" + fileName);
                    throw e;
                }
            }
        }
    }

    public static void main(String[] args) {
        try {
            String s = FileHelper.readFile(new FileInputStream(new File("d:/test.txt")));
            System.out.println(s);

            JSONObject json = JSON.parseObject(s);
            System.out.println(json.getString("a"));
            System.out.println(json.getString("b"));
            System.out.println(json.getString("c"));
        } catch (Exception e) {
            e.printStackTrace();
        }
    }
}