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;
}