import java.io.*;
import java.util.Enumeration;
import org.apache.tools.zip.ZipEntry;
import org.apache.tools.zip.ZipFile;
import org.apache.tools.zip.ZipOutputStream;
public class IOTest {
/*1.流失一组有序的数据序列 IO通常与磁盘文件存取有关
字节流以Stream结尾 字符流以reader writer结尾
* */
/*2.文件/文件夹的创建,删除*/
@Test
public void testFile() {
/*所在项目的跟路径*/
String path = "word.txt";
String dir = "hello";
File file = new File(path);
File dirFile = new File(dir);
try {
file.createNewFile();
dirFile.mkdirs();
System.out.println(file.getAbsolutePath());
System.out.println(file.getParent());
} catch (IOException e) {
e.printStackTrace();
} finally {
file.delete();
dirFile.delete();
}
}
/*3.获取文件的详细信息*/
@Test
public void testGetFileInfo() {
String path = "C:\\Windows\\System32\\drivers\\etc\\hosts";
String path2 = "C:\\Windows\\System32\\drivers\\etc\\";
System.out.println(new File(path));//构造方法1
System.out.println(new File(path2, "hosts"));//构造方法2
System.out.println(new File(new File(path2), "hosts"));//构造方法3
System.out.println(new File(path).getName());//获取文件的名称
System.out.println(new File(path).canRead()); //判断文件是否为可读的
System.out.println(new File(path).canWrite());//判断文件是否可被写入
System.out.println(new File(path).exists());//判断文件是否存在
System.out.println(new File(path).length()); //获取文件的长度(以字节为单位);//
System.out.println(new File(path).getAbsolutePath());//获取文件的绝对路径
System.out.println(new File(path).getParent());//获取文件的父路径
System.out.println(new File(path).isFile()); //判断文件是否存在
System.out.println(new File(path).isDirectory()); //判断文件是否为一个目录
System.out.println(new File(path).isHidden()); //判断文件是否为隐藏文件
System.out.println(new File(path).lastModified());//获取文件最后修改时间
}
/*4.文件输入流 输出流*/
@Test
public void testFileInputOutputStream() throws Exception {
/*创建一个文件往文件写入内容 然后读取文件内容 打印到控制台*/
File file = new File("word.txt");
FileOutputStream os = new FileOutputStream(file);
byte[] bytes = "Hello Java,Hello World".getBytes();
/*方法：将指定的字节写入此输出流。*/
os.write(bytes);
os.flush();//方法：彻底完成输出并清空缓存区。
os.close();//方法：关闭输出流。
FileInputStream in = new FileInputStream(file);
byte[] bytes1 = new byte[1024];
int length = in.read(bytes1);
System.out.println(new String(bytes1, 0, length));
in.close();//方法关闭此输入流并释放与该流关联的所有系统资源。
file.delete();
}
/*5.文件字符流 可以避免中文乱码*/
@Test
public void testFileWriterReader() throws Exception {
File file = new File("word.txt");
FileWriter fw = new FileWriter(file);
String str = "人工智能物联网大数据";
fw.write(str);
fw.flush();
fw.close();
FileReader fr = new FileReader(file);
char[] bytes1 = new char[1024];
int length = fr.read(bytes1);
System.out.println(new String(bytes1, 0, length));
fr.close();//方法关闭此输入流并释放与该流关联的所有系统资源。
file.delete();
}
/*6.缓冲流是高级流,对于低级流的封装 弥补性能的不足*/
/*BuffedInputStream BufferOutputStream
* BufferedReader BufferredWriter*/
@Test
public void testBuffer() throws Exception {
String[] strArray = {"Hadoop", "Hive", "HBase", "Spark"};
File file = new File("word.txt");
FileWriter fw = new FileWriter(file);
BufferedWriter bw = new BufferedWriter(fw);
for (String str : strArray) {
bw.write(str);
bw.newLine();/*换行*/
}
bw.close();
fw.close();
FileReader fr = new FileReader(file);
BufferedReader br = new BufferedReader(fr);
String str = null;
while ((str = br.readLine()) != null) {
System.out.println(str);
}
br.close();
fr.close();
file.delete();
}
/*7.DataInputStream/DataOutputStream在读取数据时候不关心数据的字节*/
@Test
public void testDataInputOutputStream() throws Exception {
File file = new File("word.txt");
FileOutputStream fos = new FileOutputStream(file);
DataOutputStream dos = new DataOutputStream(fos);
//3种写入字符串的方法 writeChars writeBytes writeUTF
dos.writeUTF("writeUTF");
dos.close();
FileInputStream fis = new FileInputStream(file);
DataInputStream dis = new DataInputStream(fis);
//writeUTF readUTF必须一致否则报错
System.out.println(dis.readUTF());
file.delete();
}
/*文件压缩 原生不支持中文文件目录*/
@Test
public void testZipFile() throws Exception {
unZip("cronCreator.zip");
zip("cronCreator.zip");
}
//解压指定zip文件
public static void unZip(String str) {//unZipfileName需要解压的zip文件名
FileOutputStream fos;
File file;
InputStream inputStream;
try {
ZipFile zipFile = new ZipFile(new File(str), "GBK");
for (Enumeration entries = zipFile.getEntries(); entries.hasMoreElements(); ) {
ZipEntry entry = (ZipEntry) entries.nextElement();
String tmp = str.substring(0, str.lastIndexOf("."));
if (!new File(tmp).exists()) {
new File(tmp).mkdirs();
}
file = new File(tmp + File.separator + entry.getName());
if (entry.isDirectory()) {
file.mkdirs();
} else {
//如果指定文件的目录不存在,则创建之.
File parent = new File(file.getParent());
if (!parent.exists()) {
parent.mkdirs();
}
inputStream = zipFile.getInputStream(entry);
fos = new FileOutputStream(file);
int readedBytes;
byte[] buf = new byte[1024 * 1024 * 1024];
while ((readedBytes = inputStream.read(buf)) > 0) {
fos.write(buf, 0, readedBytes);
}
fos.close();
inputStream.close();
}
}
zipFile.close();
} catch (IOException ioe) {
ioe.printStackTrace();
}
}
public static File zip(String filePath) throws Exception {
File target = null;
File source = new File(filePath);
if (source.exists()) {
// 压缩文件名=源文件名.zip
String zipName = source.getName() + ".zip";
target = new File(source.getParent(), zipName);
if (target.exists()) {
target.delete(); // 删除旧的文件
}
FileOutputStream fos = null;
ZipOutputStream zos = null;
try {
fos = new FileOutputStream(target);
zos = new ZipOutputStream(new BufferedOutputStream(fos));
// 添加对应的文件Entry
addEntry("/", source, zos);
} catch (IOException e) {
throw new RuntimeException(e);
} finally {
zos.closeEntry();
zos.close();
fos.close();
}
}
return target;
}
private static void addEntry(String base, File source, ZipOutputStream zos)
throws IOException {
// 按目录分级，形如：/aaa/bbb.txt
String entry = base + source.getName();
if (source.isDirectory()) {
for (File file : source.listFiles()) {
// 递归列出目录下的所有文件，添加文件Entry
addEntry(entry + "/", file, zos);
}
} else {
FileInputStream fis = null;
BufferedInputStream bis = null;
try {
byte[] buffer = new byte[1024 * 10];
fis = new FileInputStream(source);
bis = new BufferedInputStream(fis, buffer.length);
int read = 0;
zos.putNextEntry(new ZipEntry(entry));
while ((read = bis.read(buffer, 0, buffer.length)) != -1) {
zos.write(buffer, 0, read);
}
zos.closeEntry();
} finally {
bis.close();
fis.close();
}
}
}
}
<!-- 解压zip -->
<dependency>
<groupId>org.apache.ant</groupId>
<artifactId>ant</artifactId>
<version>1.8.4</version>
</dependency>
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