//FileReader FileWriter 读写英文
public void FileReaderAndWriter1() throws Exception {
File filePath = new File("E:/iotest");
if (!filePath.exists()) {
filePath.mkdirs();
}
//写文件
File file = new File(filePath.getPath(), "writer.txt");
FileWriter writer = new FileWriter(file);
for (int i = 0; i < 100; i++) {
writer.write(new char[]{'a','b','c'});
writer.write(new char[]{'\r','\n'});
}
writer.close();
//读取文件
FileReader reader = new FileReader(file);
char[] chars=new char[100];
int readCount =0;
while((readCount=reader.read(chars))>0){
System.out.print(String.valueOf(chars).substring(0, readCount));
}
reader.close();
}
//FileReader FileWriter 读写中文
public void FileReaderAndWriter2() throws Exception {
File filePath = new File("E:/iotest");
if (!filePath.exists()) {
filePath.mkdirs();
}
//写文件
File file = new File(filePath.getPath(), "writer.txt");
FileWriter writer = new FileWriter(file);
BufferedWriter bfWriter = new BufferedWriter(writer);
for (int i = 0; i < 10000; i++) {
bfWriter.write("当前行号" + i);
bfWriter.write("\r\n");
}
bfWriter.flush();
writer.close();
bfWriter.close();
//读取文件
FileReader reader = new FileReader(file);
BufferedReader bfReader =new BufferedReader(reader);
String line="";
while((line=bfReader.readLine())!=null){
System.out.println(line);
}
}
//FileInputStream FileOutputStream
public void FileStream() throws Exception{
File file1 =new File("E:/iotest","writer.txt");
FileInputStream input =new FileInputStream(file1);
BufferedInputStream bInput =new BufferedInputStream(input);
File file2 =new File("E:/iotest","writer1.txt");
FileOutputStream output = new FileOutputStream(file2);
BufferedOutputStream bOutput =new BufferedOutputStream(output);
byte [] b=new byte[1024];
int bCount;
while((bCount=bInput.read(b))>0){
bOutput.write(b, 0, bCount);
}
bOutput.flush();
bOutput.close();
bInput.close();
}
//BitArrayInputStream BitArrayOutputStream
public void BitStream()throws Exception{
byte [] binput =new byte[]{12,-1,127,-128,0};
ByteArrayInputStream input = new ByteArrayInputStream(binput);
int i;
while((i = input.read())!=-1){
System.out.println(i);
}
ByteArrayOutputStream output = new ByteArrayOutputStream();
output.write(new byte[]{67,97,1});
String strOut = output.toString();
System.out.println(strOut);
}
//CharArrayReader CharArrayWriter
public void CharStream()throws Exception{
CharArrayReader reader =new CharArrayReader(new char[]{'a','b','c'});
int i;
while((i=reader.read())!=-1){
System.out.println(i);
}
CharArrayWriter writer = new CharArrayWriter();
writer.write("上海");
char [] cbuf =new char[]{'a','b','c','A'};
writer.write(cbuf);
File file = new File("E:/iotest/char.txt");
FileWriter fw = new FileWriter(file);
writer.writeTo(fw);
writer.flush();
fw.flush();
}
//ObjectStream
public void ObjectStream() throws Exception{
FileOutputStream fos = new FileOutputStream("E:/iotest/object.txt");
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeDouble(10.2);
oos.writeFloat(16.323f);
oos.writeChars("中国");
Student stu =new Student(1,"cwg",new Date());
oos.writeObject(stu);
oos.flush();
oos.close();
FileInputStream fis =new FileInputStream("E:/iotest/object.txt");
ObjectInputStream ois = new ObjectInputStream(fis);
System.out.println( ois.readDouble());
System.out.println( ois.readFloat());
System.out.println( ois.readChar());
System.out.println( ois.readChar());
Object obj = ois.readObject();
if(obj instanceof Student){
Student rstu =(Student)obj;
System.out.println(rstu.getId()+"--"+rstu.getUserName());
}
}
public static void main(String[] args) throws Exception {
IODemo demo = new IODemo();
//demo.FileReaderAndWriter1();
//demo.FileReaderAndWriter2();
//demo.FileStream();
//demo.BitStream();
//demo.CharStream();
//demo.ObjectStream();
}