package com.zhang.stream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;
import java.io.RandomAccessFile;
import java.util.LinkedList;
import java.util.List;
import com.zhang.common.Common;
/**
* @Package com.zhang.stream
* @ClassName: PubFileUtil
* @Description: 讀寫有風險，操作需謹慎（注意備份）
* @author: ZhangSongbo
* @date 2014-9-28 上午11:47:42
* @version V1.0
*/
public class PubFileUtil {
private static String filePath = "d:\\EduInfo.java";
public static final String RN = "\r\n";//可替換Common.RN
/**
* @Title: readFileList
* @Description: 所給目錄下的所有檔案名稱集合
* @param @param filepath 檔案路徑
* @param @return 傳回目前路徑下所有檔案名稱集合
* @return List<String>
* @throws IOException
*/
public static List<String> readFileList(String filepath) throws IOException {
List<String> list = new LinkedList<String>();
try {
File file = new File(filepath);
if (!file.isDirectory()) {
System.out.println("檔案");
System.out.println("path=" + file.getPath());
System.out.println("absolutepath=" + file.getAbsolutePath());
System.out.println("name=" + file.getName());
} else if (file.isDirectory()) {
System.out.println("檔案夾");
String[] filelist = file.list();
for (int i = 0; i < filelist.length; i++) {
File readfile = new File(filepath + "\\" + filelist[i]);
if (!readfile.isDirectory()) {
list.add(readfile.getName());
} else if (readfile.isDirectory()) {
readFileList(filepath + "\\" + filelist[i]);
System.out.println(filepath + "\\" + filelist[i]);
}
}
}
} catch (FileNotFoundException e) {
e.printStackTrace();
}
System.out.println(list);
return list;
}
/**
* @Title: randomAccessWrite
* @Description: 随機流寫操作
* @param @param filePath 檔案路徑
* @param @param content 追加的内容
* @return void
* @throws IOException
*/
public static void randomAccessWrite(String filePath, String content) {
File fileName = new File(filePath);
RandomAccessFile randomFile = null;
try {
// 打開一個随機通路檔案流，按讀寫方式
randomFile = new RandomAccessFile(fileName, "rw");
// 檔案長度，位元組數
long fileLength = randomFile.length();
// 将寫檔案指針移到檔案尾。
// byte[] buffer = new byte[1024];
randomFile.seek(fileLength);
randomFile.write(content.getBytes());
System.out.println("操作完成！");
} catch (IOException e) {
e.printStackTrace();
} finally {
if (randomFile != null) {
try {
randomFile.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
/**
* @Title: findLines
* @Description: TODO
* @param @param filePath 檔案路徑
* @param @param context 查找的字元串
* @param @return 包含搜尋的字元串的行
* @param @throws IOException
* @return List<String>
*/
public static List<String> findLines(String filePath, String context) throws IOException {
List<String> list = new LinkedList<String>();
BufferedReader read = new BufferedReader(new FileReader(filePath));
String str = null;
while ((str = read.readLine()) != null) {
if (str.indexOf(context) != -1) {
list.add(str);
}
}
read.close();
return list;
}
/**
* @Title: findParagraph
* @Description: 根據查找字元串劃分内容（第一個符合的字元串對象有效）
* @param @param filePath 檔案路徑
* @param @param context 查找的字元串
* @param @return List<String>
* @param @throws IOException
* @return List<String>
* @throws
*/
public static List<String> findParagraph(String filePath, String context) throws IOException {
BufferedReader read = new BufferedReader(new FileReader(filePath));
List<String> list = new LinkedList<String>();
String paragraphHead = "";
String paragraphEnd = "";
String line = "";
int index = 0;
int lineNum=1;
while ((line = read.readLine()) != null) {
if (index == 0) {
paragraphHead += (line + Common.RN);
}
if (line.indexOf(context) != -1 && index == 0) {
System.out.println("行号："+lineNum+"，目前行内容: "+line);
list.add(paragraphHead);
index++;
continue;
}
if (index > 0) {
paragraphEnd += (line + Common.RN);
}
lineNum++;
}
list.add(paragraphEnd);
read.close();
return list;
}
/**
* @Title: writeFile
* @Description: TODO
* @param @param filePath 檔案路徑名稱
* @param @param context要寫入的檔案内容
* @param @param codeType編碼格式（預設為utf-8）
* @param @throws IOException
* @return void
* @throws IOException
*/
public static void writeFile(String filePath, String context, String codeType) throws IOException {
File f = new File(filePath);
InputStreamReader read = null;
if (codeType != null && !codeType.trim().equals("")) {
read = new InputStreamReader(new FileInputStream(f), codeType);
} else {
read = new InputStreamReader(new FileInputStream(f), "UTF-8");
}
BufferedReader reader = new BufferedReader(read);
String line = "";
String str = "";
while ((line = reader.readLine()) != null) {
str += (line + Common.RN);
}
OutputStream out = new FileOutputStream(f);
byte[] bt = context.getBytes();
out.write(bt);
out.flush();
out.close();
System.out.println("讀取檔案結束！" + Common.RN + "開始向檔案開始追加内容" + Common.RN + str);
randomAccessWrite(filePath, str);
}
/**
* @Title: writeParagraph
* @Description: TODO
* @param @param filePath 路徑
* @param @param context 要查找的字元串
* @param @param wcontext要寫入的内容
* @param @param codeType 編碼格式（預設utf-8）
* @param @throws IOException
* @return void
* @throws
*/
public static void writeParagraph(String filePath, String context, String wcontext, String codeType) throws IOException {
File fileName = new File(filePath);
List<String> list = findParagraph(filePath, context);
RandomAccessFile randomFile = null;
OutputStreamWriter write = null;
if (codeType != null && !codeType.trim().equals("")) {
write = new OutputStreamWriter(new FileOutputStream(fileName), codeType);
} else {
write = new OutputStreamWriter(new FileOutputStream(fileName), "utf-8");
}
//清空檔案内容
write.write("");
write.close();
try {
// 打開一個随機通路檔案流，按讀寫方式
randomFile = new RandomAccessFile(fileName, "rw");
int index=0;
for (int i = 0; i < list.size(); i++) {
if (index==0) {
randomFile.write(list.get(i).getBytes());
randomFile.write((wcontext + Common.RN).getBytes());
}
if (index>0) {
randomFile.write(list.get(i).getBytes());
}
index++;
}
System.out.println("操作完成！");
} catch (IOException e) {
e.printStackTrace();
} finally {
if (randomFile != null) {
try {
randomFile.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
public static void main(String[] args) throws IOException {
long startTime = System.currentTimeMillis();
writeParagraph( filePath, "{", "做人要像陳冠希，随時帶好照相機！", null);
long endTime= System.currentTimeMillis();
System.out.println("time:"+(endTime-startTime)+"ms");
//readFileList("D:\\Workspaces\\dao\\src");
}
}
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