Java:逐行读、写文件、文件目录过滤的用法

import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.InputStreamReader;
import java.util.ArrayList;
import java.util.List;

public class HelloWord {
    public static void main(String[] args) throws IOException {
        String filePath = "my File.txt";
        File file = new File(filePath);
        InputStreamReader inputStreamReader = new InputStreamReader(new FileInputStream(file),"utf-8");
        BufferedReader bufferedReader = new BufferedReader(inputStreamReader);

        List<String> lineItems=new ArrayList<String>();
        String line = null;
        while ((line = bufferedReader.readLine()) != null) {
            String[] items = line.split(",");
            
            String item= items[1];
            if(item.indexOf("花园")!=-1){
                lineItems.add(line);
            }
        }

        bufferedReader.close();
        inputStreamReader.close();
        
        for(String my : lineItems){
            System.out.println(my);
        }
    }
}

写文件用法：

　　　　 List<String> lines = new ArrayList<>();
　　　　 String wfilePath="e:\1.txt";
        File wfile = new File(wfilePath);
        OutputStreamWriter outputStreamWriter = new OutputStreamWriter(new FileOutputStream(wfile), "utf-8");
        BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
        for (String eLine : lines) {
            bufferedWriter.write(eLine);
            bufferedWriter.newLine();
        }

        bufferedWriter.close();
        outputStreamWriter.close();
        
        System.out.println("Complete...");

实例：

  1 package com.dx.hibernate5.test;
  2 
  3 import java.io.BufferedReader;
  4 import java.io.BufferedWriter;
  5 import java.io.File;
  6 import java.io.FileInputStream;
  7 import java.io.FileNotFoundException;
  8 import java.io.FileOutputStream;
  9 import java.io.IOException;
 10 import java.io.InputStreamReader;
 11 import java.io.OutputStreamWriter;
 12 import java.io.UnsupportedEncodingException;
 13 import java.util.ArrayList;
 14 import java.util.HashMap;
 15 import java.util.List;
 16 import java.util.Map;
 17 
 18 public class HelloWord {
 19     public static void main(String[] args) throws IOException {
 20         String filePath = "E:\丽水";
 21         String wfilePath = "E:\丽水_New";
 22         parserCountyVsCode(filePath);
 23 
 24         parseCityCounty(filePath, wfilePath);
 25 
 26         System.out.println("Complete...");
 27     }
 28 
 29     private static void parserCountyVsCode(String filePath)
 30             throws UnsupportedEncodingException, FileNotFoundException, IOException {
 31         File file = new File(filePath);
 32         InputStreamReader inputStreamReader = new InputStreamReader(new FileInputStream(file), "utf-8");
 33         BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
 34         // 缙云县:5782
 35         // 云和县:5784
 36         // 开发区:578B
 37         // 龙泉市:5786
 38         // 景宁县:5789
 39         // 青田县:5783
 40         // 景宁畲族自治县:5789
 41         // 松阳县:5788
 42         // 庆元县:5785
 43         // 莲都区:5781
 44         // 遂昌县:5787
 45         List<String> countyList = new ArrayList<>();
 46         countyList.add("5782");
 47         countyList.add("5784");
 48         countyList.add("578B");
 49         countyList.add("5786");
 50         countyList.add("5789");
 51         countyList.add("5783");
 52         countyList.add("5788");
 53         countyList.add("5785");
 54         countyList.add("5781");
 55         countyList.add("5787");
 56 
 57         Map<String, String> lineItems = new HashMap<String, String>();
 58         String line = null;
 59         while ((line = bufferedReader.readLine()) != null) {
 60             String[] items = line.split(",");
 61 
 62             String address = items[3];
 63             String county = items[2];
 64         
 65             if (address.indexOf("莲都区") != -1) {
 66                 lineItems.put("莲都区", county);
 67             } else if (address.indexOf("开发区") != -1) {
 68                 lineItems.put("开发区", county);
 69             } else if (address.indexOf("青田县") != -1) {
 70                 lineItems.put("青田县", county);
 71             } else if (address.indexOf("缙云县") != -1) {
 72                 lineItems.put("缙云县", county);
 73             } else if (address.indexOf("遂昌县") != -1) {
 74                 lineItems.put("遂昌县", county);
 75             } else if (address.indexOf("松阳县") != -1) {
 76                 lineItems.put("松阳县", county);
 77             } else if (address.indexOf("云和县") != -1) {
 78                 lineItems.put("云和县", county);
 79             } else if (address.indexOf("庆元县") != -1) {
 80                 lineItems.put("庆元县", county);
 81             } else if (address.indexOf("景宁县") != -1 || address.indexOf("景宁畲族自治县") != -1) {
 82                 lineItems.put("景宁县", county);
 83             } else if (address.indexOf("龙泉市") != -1) {
 84                 lineItems.put("龙泉市", county);
 85             } else {
 86                 Boolean hasContains = false;
 87                 for (String coun : countyList) {
 88                     if (coun.equals(county)) {
 89                         hasContains = true;
 90                     }
 91                 }
 92                 if (!hasContains) {
 93                     System.out.println(line);
 94                 }
 95             }
 96         }
 97 
 98         bufferedReader.close();
 99         inputStreamReader.close();
100 
101         for (Map.Entry<String, String> kvEntry : lineItems.entrySet()) {
102             System.out.println(kvEntry.getKey() + ":" + kvEntry.getValue());
103         }
104     }
105 
106     private static void parseCityCounty(String filePath, String wfilePath)
107             throws UnsupportedEncodingException, FileNotFoundException, IOException {
108         Map<String, String> idVsCountry = new HashMap<>();
109         idVsCountry.put("5782", "缙云县");
110         idVsCountry.put("5784", "云和县");
111         idVsCountry.put("578B", "开发区");
112         idVsCountry.put("5786", "龙泉市");
113         idVsCountry.put("5789", "景宁县");
114         idVsCountry.put("5783", "青田县");
115         idVsCountry.put("5788", "松阳县");
116         idVsCountry.put("5785", "庆元县");
117         idVsCountry.put("5781", "莲都区");
118         idVsCountry.put("5787", "遂昌县");
119 
120         List<String> lines = new ArrayList<>();
121         lines.add("abc0");
122         lines.add("abc1");
123         lines.add("abc2");
124         File file = new File(filePath);
125         InputStreamReader inputStreamReader = new InputStreamReader(new FileInputStream(file), "utf-8");
126         BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
127         String line = null;
128         while ((line = bufferedReader.readLine()) != null) {
129             String[] items = line.split(",");
130 
131             String address = items[3];
132             String county = items[2];
133             String newLine = items[0] + ",丽水市," + idVsCountry.get(county) + "," + address;
134             // System.out.println(newLine);
135             lines.add(newLine);
136         }
137 
138         bufferedReader.close();
139         inputStreamReader.close();
140 
141         File wfile = new File(wfilePath);
142         OutputStreamWriter outputStreamWriter = new OutputStreamWriter(new FileOutputStream(wfile), "utf-8");
143         BufferedWriter bufferedWriter = new BufferedWriter(outputStreamWriter);
144         for (String eLine : lines) {
145             bufferedWriter.write(eLine);
146             bufferedWriter.newLine();
147         }
148 
149         bufferedWriter.close();
150         outputStreamWriter.close();
151     }
152 }

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原文地址：https://www.cnblogs.com/yy3b2007com/p/6708446.html