Java IO实战操作(四)

/** * 文件压缩 ZipOutputStream类 * @throws IOException */ public void ZipOutputStreamFile() throws IOException { File file = new File("d:" + File.separator + "hello.txt"); File zipFile = new File("d:" + File.separator + "hello.zip"); InputStream input = new FileInputStream(file); ZipOutputStream zipOut = new ZipOutputStream(new FileOutputStream( zipFile)); zipOut.putNextEntry(new ZipEntry(file.getName())); // 设置注释 zipOut.setComment("hello"); int temp = 0; while ((temp = input.read()) != -1) { zipOut.write(temp); } input.close(); zipOut.close(); } /** * 多个文件的压缩 * @throws IOException */ public void ZipOutputStreamFiles() throws IOException { // 要被压缩的文件夹 File file = new File("d:" + File.separator + "temp"); //temp文件夹下面的所有文件 File zipFile = new File("d:" + File.separator + "zipFile.zip"); InputStream input = null; ZipOutputStream zipOut = new ZipOutputStream(new FileOutputStream(zipFile)); zipOut.setComment("hello"); if (file.isDirectory()) { File[] files = file.listFiles(); for (int i = 0; i < files.length; ++i) { input = new FileInputStream(files[i]); zipOut.putNextEntry(new ZipEntry(file.getName() + File.separator + files[i].getName())); int temp = 0; while ((temp = input.read()) != -1) { zipOut.write(temp); } input.close(); } } zipOut.close(); } /** * ZipFile演示 * @throws IOException * @throws ZipException */ public void ZipFileDemo() throws ZipException, IOException{ File file = new File("d:" + File.separator + "hello.zip"); ZipFile zipFile = new ZipFile(file); System.out.println("压缩文件的名称为：" + zipFile.getName()); } /** * 解压缩文件（压缩文件中只有一个文件的情况） * @throws IOException * @throws ZipException */ public void ZipFileOutOne() throws ZipException, IOException{ File file = new File("d:" + File.separator + "hello.zip"); File outFile = new File("d:" + File.separator + "unZipFile.txt"); ZipFile zipFile = new ZipFile(file); ZipEntry entry = zipFile.getEntry("hello.txt"); InputStream input = zipFile.getInputStream(entry); OutputStream output = new FileOutputStream(outFile); int temp = 0; while((temp = input.read()) != -1){ output.write(temp); } input.close(); output.close(); } /** * ZipInputStream解压多个文件 * @throws IOException * @throws ZipException */ public void ZipInputStreams() throws ZipException, IOException{ File file = new File("d:" + File.separator + "zipFile.zip"); File outFile = null; ZipFile zipFile = new ZipFile(file); ZipInputStream zipInput = new ZipInputStream(new FileInputStream(file)); ZipEntry entry = null; InputStream input = null; OutputStream output = null; while((entry = zipInput.getNextEntry()) != null){ System.out.println("解压缩" + entry.getName() + "文件"); outFile = new File("d:" + File.separator + entry.getName()); if(!outFile.getParentFile().exists()){ outFile.getParentFile().mkdir(); } if(!outFile.exists()){ outFile.createNewFile(); } input = zipFile.getInputStream(entry); output = new FileOutputStream(outFile); int temp = 0; while((temp = input.read()) != -1){ output.write(temp); } input.close(); output.close(); } } /** * PushBackInputStream退回流 * @throws IOException */ public void PushBackInputStreamFile() throws IOException{ String str = "hello,rollenholt"; PushbackInputStream push = null; ByteArrayInputStream bat = null; bat = new ByteArrayInputStream(str.getBytes()); push = new PushbackInputStream(bat); int temp = 0; while((temp = push.read()) != -1){ if(temp == ','){ push.unread(temp); temp = push.read(); System.out.print("(回退" + (char) temp + ") "); }else{ System.out.print((char) temp); } } /** * 取得本地的默认编码 * */ System.out.println("系统默认编码为：" + System.getProperty("file.encoding")); } } /** * 文件序列化 */ public void SserializeFile() throws FileNotFoundException, IOException, ClassNotFoundException { // 打开是乱码必须使用ObjectInputStream查看 File file = new File("d:" + File.separator + "hello.txt"); ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream( file)); oos.writeObject(new SerializableDemo("rollen", 20)); oos.close(); /** * ObjectInputStream示范 * */ ObjectInputStream input = new ObjectInputStream(new FileInputStream( file)); Object obj = input.readObject(); input.close(); System.out.println(obj); } /** *****序列化与反序列化*********** */ // 序列化 public void ser() throws Exception { File file = new File("d:" + File.separator + "hello.txt"); ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream( file)); out.writeObject(new Person("rollen", 20)); out.close(); } // 反序列化 public void dser() throws Exception { File file = new File("d:" + File.separator + "hello.txt"); ObjectInputStream input = new ObjectInputStream(new FileInputStream(file)); Object obj = input.readObject(); input.close(); System.out.println(obj); } /** * 实现具有序列化能力的类 * */ class SerializableDemo implements Serializable { public SerializableDemo() { } public SerializableDemo(String name, int age) { this.name = name; this.age = age; } @Override public String toString() { return "姓名：" + name + " 年龄：" + age; } private String name; private int age; } class Person implements Externalizable { public Person() { } public Person(String name, int age) { this.name = name; this.age = age; } @Override public String toString() { return "姓名：" + name + " 年龄：" + age; } // 复写这个方法，根据需要可以保存的属性或者具体内容，在序列化的时候使用 public void writeExternal(ObjectOutput out) throws IOException { out.writeObject(this.name); out.writeInt(age); } // 复写这个方法，根据需要读取内容 反序列话的时候需要 public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException { this.name = (String) in.readObject(); this.age = in.readInt(); } private String name; // 加上transient关键字可以不序列化 // private transient String name; private int age; /** * 序列化一组对象 * @param args * @throws Exception */ public static void main(String[] args) throws Exception { Student[] stu = { new Student("hello", 20), new Student("world", 30), new Student("rollen", 40) }; ser(stu); Object[] obj = dser(); for (int i = 0; i < obj.length; ++i) { Student s = (Student) obj[i]; System.out.println(s); } } // 序列化 public static void ser(Object[] obj) throws Exception { File file = new File("d:" + File.separator + "hello.txt"); ObjectOutputStream out = new ObjectOutputStream(new FileOutputStream( file)); out.writeObject(obj); out.close(); } // 反序列化 public static Object[] dser() throws Exception { File file = new File("d:" + File.separator + "hello.txt"); ObjectInputStream input = new ObjectInputStream(new FileInputStream(file)); Object[] obj = (Object[]) input.readObject(); input.close(); return obj; } } class Student implements Serializable { public Student() { } public Student(String name, int age) { this.name = name; this.age = age; } @Override public String toString() { return "姓名： " + name + " 年龄：" + age; } private String name; private int age; }