com.ulitis.www

package com.ulitis.www;

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileReader;
import java.io.FileWriter;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;

public class JUtils {

    // Read one from Spec Layout
    public static String readFromFile(String filename)
            throws FileNotFoundException, IOException {
        FileInputStream fis = new FileInputStream(filename);
        InputStreamReader isr = new InputStreamReader(fis, "UTF-8");
        BufferedReader br = new BufferedReader(isr);
        // 简写如下
        // BufferedReader br = new BufferedReader(new InputStreamReader(
        // new FileInputStream("E:/phsftp/evdokey/evdokey_201103221556.txt"),
        // "UTF-8"));
        String line = "";
        String arrs = null;
        while ((line = br.readLine()) != null) {
            arrs += line;
        }
        br.close();
        isr.close();
        fis.close();
        return arrs;
    }

    public static void write(String path, String content) {
        String s = new String();
        String s1 = new String();

        try {
            File f = new File(path);

            if (f.exists()) {
                System.out.println("文件存在");
                if (f.delete()) {
                    f.createNewFile();
                    System.out.println("文件删除成功!");
                } else {
                    System.out.println("文件删除失败!");
                }

            } else {
                System.out.println("文件不存在,正在创建...");
                if (f.createNewFile()) {
                    System.out.println("文件创建成功!");
                } else {
                    System.out.println("文件创建失败!");
                }
            }
            
            BufferedReader input = new BufferedReader(new FileReader(f));

            while ((s = input.readLine()) != null) {
                s1 += s + "/n";
                
            }

            input.close();
            s1 += content;
            BufferedWriter output = new BufferedWriter(new FileWriter(f));
            output.write(s1);
            output.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    // format for if condition
    public static String getFormat(int i) {
        return i + "****";
    }

}
package com.ulitis.www;

import java.io.BufferedInputStream;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.util.Enumeration;
import java.util.LinkedHashMap;
import java.util.Map;
import java.util.Properties;

public class PropertiesUnit {
     private static LinkedHashMap<String,String> map = new LinkedHashMap<String,String>();
     public static String readValue(String filePath,String key) {
           Properties props = new Properties();
                 try {
                  InputStream in = new BufferedInputStream (new FileInputStream(filePath));
                  props.load(in);
                  String value = props.getProperty (key);
                     System.out.println(key+value);
                     return value;
                 } catch (Exception e) {
                  e.printStackTrace();
                  return null;
                 }
          }
          
          //读取properties的全部信息
            public static LinkedHashMap<String, String> readProperties(String filePath) {
              Properties props = new Properties();
                 try {
                  InputStream in = new BufferedInputStream (new FileInputStream(filePath));
                  props.load(in);
                     Enumeration en = props.propertyNames();
                      while (en.hasMoreElements()) {
                               String key = (String) en.nextElement();
                             String Property = props.getProperty (key);
               
                             map.put(key, Property);
                             
                         }
                 } catch (Exception e) {
                  e.printStackTrace();
                 }
                 return map;
             }

            //写入properties信息
            public static void writeProperties(String filePath,String parameterName,String parameterValue) {
              Properties prop = new Properties();
              try {
               InputStream fis = new FileInputStream(filePath);
                     //从输入流中读取属性列表(键和元素对)
                    prop.load(fis);
                     //调用 Hashtable 的方法 put。使用 getProperty 方法提供并行性。
                    //强制要求为属性的键和值使用字符串。返回值是 Hashtable 调用 put 的结果。
                    OutputStream fos = new FileOutputStream(filePath);
                     prop.setProperty(parameterName, parameterValue);
                     //以适合使用 load 方法加载到 Properties 表中的格式,
                    //将此 Properties 表中的属性列表(键和元素对)写入输出流
                    prop.store(fos, "Update '" + parameterName + "' value");
                 } catch (IOException e) {
                  System.err.println("Visit "+filePath+" for updating "+parameterName+" value error");
                 }
             }

}
原文地址:https://www.cnblogs.com/MarchThree/p/3655503.html