黑马程序员 java IO FileReader FileWriter 文件操作

public class I_04_IO {


/**
* @param args
*/
static String path = "C:\\Users\\Administrator\\Desktop\\";
static String fileName = "fileWriter.txt";


public static void main(String[] args) {
String fileContent = "fileWriter你好\r\n";


// fileWriter(fileName, fileContent, false);
//
// fileReader(fileName);
//
// fileReaderArr(fileName);


bufferedWriter(fileName);


}


private static void bufferedWriter(String fileName) {
BufferedReader br = null;
try {
br = new BufferedReader(new FileReader(path + fileName));
String str = null;
while ((str = br.readLine()) != null) {
System.out.println(str);
}
;
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}


/*
* 一个数组一个数组读文件
*/
private static void fileReaderArr(String fileName) {
FileReader fr = null;
char[] buff = new char[1024];
int number = -1;
String contentText = null;
try {
fr = new FileReader(path + fileName);
while ((number = fr.read(buff)) != -1) {
contentText = new String(buff, 0, number);
}
} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (fr != null)
fr.close();
} catch (IOException e) {
e.printStackTrace();
}
}
System.out.println(contentText);
}


/*
* 一个字符的读文件
*/
private static void fileReader(String fileName) {
String allText = null;
FileReader fr = null;
try {
fr = new FileReader(path + fileName);
int flag = -1;
while ((flag = fr.read()) != -1) {
allText += (char) flag;
}


} catch (FileNotFoundException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (fr != null)
fr.close();
} catch (IOException e) {
e.printStackTrace();
}
}
System.out.println(allText);
}


/*
* 
* 写文件
*/
private static void fileWriter(String fileName, String text, boolean append) {
FileWriter fw = null;// 对象一创建就创建文件
try {
fw = new FileWriter(path + fileName, append);
fw.write(text);
} catch (IOException e) {
e.printStackTrace();
} finally {
try {
if (fw != null)
fw.close();
} catch (IOException e) {
e.printStackTrace();
}
}
System.out.println("fileWriter end");
}


}