다른 프로젝트에서 output한 것을
input하는 경우
패키지 이름,클래스이름까지 같은 직렬화클래스가 있어야
ClassNotFoundException이 발생하지 않는다.
클래스 이름 = 패키지이름.클래스이름
package f10_object;
import java.io.*;
import java.util.Arrays;
public class ObjectStreamExample {
public static void main(String[] args) {
// dat : 확인할 수 없는 파일(2진으로표현)이라고 알려주는 확장자
try( // try with resources try블럭 끝나면 자동으로 외부자원 해제
FileInputStream fis = new FileInputStream("object.dat");
BufferedInputStream bis = new BufferedInputStream(fis);
ObjectInputStream ois = new ObjectInputStream(bis);
FileOutputStream fos = new FileOutputStream("object.dat");
BufferedOutputStream bos = new BufferedOutputStream(fos);
ObjectOutputStream oos = new ObjectOutputStream(bos);
){
//try
oos.writeObject(new Integer(100));
oos.writeObject(Double.valueOf(3.14));
oos.writeObject(new int[] {1,2,3,4});
oos.writeObject(new String("최기근"));
oos.flush();
Integer obj1 = (Integer)ois.readObject();
Double obj2 = (Double)ois.readObject();
int[] obj3 = (int[])ois.readObject();
String obj4 = (String)ois.readObject();
System.out.println(obj1);
System.out.println(obj2);
System.out.println(Arrays.toString(obj3));
System.out.println(obj4);
}catch(IOException | ClassNotFoundException e) {
e.printStackTrace();
}
}
}
package f10_object.serializable;
import java.io.Serializable;
public class Person implements Serializable{
private static final long serialVersionUID = 6131082771311808494L;
private String name;
// 직렬화 필드에서 제외
transient private int age;
private String phone;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
public String getPhone() {
return phone;
}
public void setPhone(String phone) {
this.phone = phone;
}
@Override
public String toString() {
return "Person [name=" + name + ", phone=" + phone + "]";
}
}
package f10_object.serializable;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
public class ObjectOutputStreamAppend extends ObjectOutputStream{
public ObjectOutputStreamAppend(OutputStream out) throws IOException {
super(out);
}
@Override
protected void writeStreamHeader() throws IOException {
// 아무 일도 하지 않음 - 헤더 정보 추가 x
}
}
package f10_object.serializable;
import java.io.File;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectOutputStream;
import java.io.OutputStream;
public class ObjectOutputExample {
public static void main(String[] args) {
File file = new File("C:\\temp\\person");
if(!file.exists()) {
file.mkdirs();
}
file = new File(file,"person.dat");
try {
OutputStream os = new FileOutputStream(file,true);
//이어서 작성하려면 헤더정보가 추가되지 않도록 ObjectOutputStreamAppend 따로 추가해서
// writeStreamHeader 오버라이딩 해줌
ObjectOutputStream oos = null;
if(!file.exists() || file.length() == 0 ) {
System.out.println("New");
oos= new ObjectOutputStream(os);
}else {
System.out.println("Append");
oos= new ObjectOutputStreamAppend(os);
}
Person person = new Person();
person.setName("이순신2");
person.setAge(500);
person.setPhone("01012345678");
oos.writeObject(person);
Person p1 = new Person();
p1.setName("최기근2");
p1.setAge(26);
p1.setPhone("01094867166");
oos.writeObject(p1);
oos.flush();
oos.close();
System.out.println("완료");
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
package f10_object.versionuid;
import java.io.Serializable;
public class ClassA implements Serializable{
/**
*
*/
private static final long serialVersionUID = -989570321322205133L;
int field1;
int field2;
String name;
}
package f10_object.versionuid;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.ObjectInputStream;
public class InputExample {
public static void main(String[] args) {
try {
ObjectInputStream ois
= new ObjectInputStream(new FileInputStream("uid.dat"));
ClassA a = (ClassA)ois.readObject();
System.out.println(a.field1);
System.out.println(a.field2);
System.out.println(a.name);
ois.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
package f10_object.versionuid;
import java.io.*;
public class OutputExample {
public static void main(String[] args) {
try {
FileOutputStream fos = new FileOutputStream("uid.dat");
ObjectOutputStream oos = new ObjectOutputStream(fos);
ClassA a = new ClassA();
a.field1 = 1;
a.field2 = 3;
oos.writeObject(a);
oos.flush();
oos.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
package f10_object.serializable;
import java.io.Serializable;
public class Person implements Serializable{
private static final long serialVersionUID = 6131082771311808494L;
private String name;
private int age;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return age;
}
public void setAge(int age) {
this.age = age;
}
@Override
public String toString() {
return "Person [name=" + name + ", age=" + age + "]";
}
}
package f10_object.serializable;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStream;
import java.io.ObjectInputStream;
import java.util.ArrayList;
import java.util.List;
public class InputExample {
public static void main(String[] args) {
File file = new File("C:\\Temp\\person\\person.dat");
if(!file.exists()) {
System.out.println("파일이 존재하지 않습니다. 확인 후 시도하세요.");
return;
}
try {
InputStream fis = new FileInputStream(file);
System.out.println(fis.available());
ObjectInputStream ois = new ObjectInputStream(fis);
System.out.println(ois.available());
List<Person> pList = new ArrayList<>();
while(fis.available() != 0) {
Person p = (Person) ois.readObject();
pList.add(p);
}
System.out.println(pList.size());
System.out.println(pList);
ois.close();
} catch (FileNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (IOException e) {
// TODO Auto-generated catch block
e.printStackTrace();
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
}
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