一、IO流的分類
字符流
Reader
InputStreamReader（節點流）
BufferedReader（處理流）
Writer
OutputStreamWriter（節點流）
BufferedWriter（處理流）
PrintWriter
字節流
InputStream
FileInputStream（節點流）
BufferedInputStream（處理流）
ObjectInputStream（處理流）
PrintStream
OutputStream
FileOutputStream（節點流）
BufferedOutputStream（處理流）
ObjectOutputStream（處理流）
斷點處理的流
RandomAccessfile
二、IO流的用法
1、轉換流的用法
|
1
2
3
4
|
FileInputStream in = new FileInputStream(newFile("")); Readerreader = new InputStreamReader(in);//字節轉字符 FileOutputStreamout = new FileOutputStream(newFile("")); Writer writer = new OutputStreamWriter(out);//字符轉字節 |
2、對象序列化,對象需要實現Serializable接口
|
1
2
3
4
5
6
7
8
9
|
FileOutputStreamfileOutputStream = new FileOutputStream("C:\\Users\\lx\\Desktop\\Record.txt");ObjectOutputStreamobjectOutputStream = new ObjectOutputStream(fileOutputStream);objectOutputStream.writeObject(object);//向指定文件寫入對象objectobjectOutputStream.close();FileInputStreamfileInputStream = new FileInputStream("C:\\Users\\lx\\Desktop\\Record.txt");ObjectInputStreamobjectInputStream = new ObjectInputStream(fileInputStream);object = objectInputStream.readObject();//讀取得到對象objectfileInputStream . lose(); |
3、斷點的運用
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
|
public class Copy extends Thread{ //可以利用多線程實現拷貝 longstart; longend; Filesorce; Filetargetdir; publicCopy() { } publicCopy(longstart,long end, File sorce, File targetdir) { //利用構造方法傳遞需要拷貝的長度，拷貝開始位置，以及目標文件和源文件 super(); this.start= start; this.end= end; this.sorce= sorce; this.targetdir= targetdir; } @Override publicvoid run(){ try{ RandomAccessFilesouceRaf = new RandomAccessFile(sorce,"r"); RandomAccessFiletargetRaf = new RandomAccessFile(newFile(targetdir,sorce.getName()),"rw"); souceRaf.seek(start); targetRaf.seek(start); intlen= 0; byte[]bs = new byte[1024]; longseek; System.out.println(start+"---->"+end+this.getName()); while((len= souceRaf.read(bs))!=-1){ targetRaf.write(bs, 0, len); seek= souceRaf.getFilePointer(); //獲取斷點位置 if(seek== end){ break; } } targetRaf.close(); souceRaf.close(); } catch (IOException e) { e.printStackTrace(); } }} |
4、字節流的用法
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
|
public class Test_InputStream { //利用字節流獲取文本文件內容，但是容易出現問題 /* //可能出現int長度越界 public static void main(String[] args) throws IOException { InputStream inputStream = new FileInputStream(new File("C:\\Users\\lx\\Desktop\\test\\33.txt")); byte[] b = new byte[inputStream.available()]; inputStream.read(b); String str = new String(b); System.out.println(str); }*/ //可能出現亂碼 public static void main(String[] args) throws IOException { File file = new File("C:\\Users\\lx\\Desktop\\test\\33.txt"); InputStream inputStream = new FileInputStream(file); //統計每次讀取的實際長度 int len = 0; //聲明每次讀取1024個字節 byte[] b = new byte[2]; StringBuffer sBuffer = new StringBuffer(); while((len=inputStream.read(b))!=-1){ sBuffer.append(new String(b,0,len)); } System.out.println(sBuffer.toString()); }}//利用字節流拷貝文件public void copy(File sourceFile, File targetDir) { // FileInputStreamfileInputStream = null; FileOutputStreamfileOutputStream = null; fileInputStream= new FileInputStream(sourceFile); FiletargetFile = new File(targetDir,sourceFile.getName()); fileOutputStream= new FileOutputStream(targetFile); byte[]b = new byte[1024]; intlen = 0; while((len= fileInputStream.read(b)) != -1) { fileOutputStream.write(b, 0, len); }} |
5、緩存字符流的用法
|
1
2
3
4
5
6
7
8
9
10
11
12
13
14
|
publicstatic void main(String[] args) throws IOException { //緩存字符流實現寫入文件 InputStreamin = System.in; Readerreader = new InputStreamReader(in); BufferedReaderbr = new BufferedReader(reader); BufferedWriterbw = new BufferedWriter(new FileWriter(new File("src/1.txt"))); Strings=""; while((s=br.readLine())!=null) { bw.write(s); bw.newLine(); bw.flush(); //字符流千萬不要忘了flush!!!!!!!!!!!!!!!!!!!!!!!!!!!!! }} |
總結
以上就是本文關于Java IO流相關知識代碼解析的全部內容，希望對大家有所幫助。感興趣的朋友可以繼續參閱本站其他相關專題，如有不足之處，歡迎留言指出。感謝朋友們對本站的支持！
原文鏈接：http://blog.csdn.net/qq_24065713/article/details/76407833
