摘自http://blog.csdn.net/fjdingsd/article/details/46765803
使用ObjectInputStream的readObject()方法如何判断读取到多个对象的结尾
import java.io.EOFException;
import java.io.FileInputStream;
import java.io.IOException;
import java.io.ObjectInputStream; import cn.com.mybolg.bean.Person; /*
* 若文件中有若干个Object对象，你用ObjectInputStream中的readObject()去读，何时判读到结尾？
* 方法之一：（常用的方法）将若干个对象（数量不定）都装入一个容器中（如：ArrayList之类），
* 然后将容器这一个对象写入就行了。读取时，只要读取一个对象（即容器对象）就行了。
*
* 方法之二：（若不想用容器），则由于数量不定，正是用EOFException来判断结束。
* 代码结构如下：(无论是readInt()读int，还是readObject()读对象)
* try{
* while(true) {
* Object o=ois.radObject();
* 处理已读出的对象o;
* }
* }
* catch(EOFException e){
* //已从流中读完。
* }
* finallly {
* 流的关闭。 }
*/ public class ObjectInputStreamDemo { public static void main(String[] args) throws IOException, ClassNotFoundException { FileInputStream fis = new FileInputStream("F:\\person.object");
ObjectInputStream osi = new ObjectInputStream(fis); try {
while(true) {
Person p = (Person) osi.readObject();
System.out.println(p.getName()+":"+p.getAge());
}
}
catch(EOFException e) { }
finally {
osi.close();
}
} }
以下是自己的试验：
往文件里存多个对象也没问题，调用writeObject()一直往里写即可，readObject()一次返回一个对象，再readObject()一次返回第二个对象，自动在每个对象后面做标记。并且同一个文件中可以依次存入不同类的对象。先存入一个Person对象，再存入一个Demo对象，再存个Haha对象都可以。按顺序读就行了。
package packa; import java.io.*; class ObjectInputOutputStream
{
public static void main(String[] args)throws Exception
{
writeObj();
readObj();
} private static void writeObj()throws Exception
{
ObjectOutputStream oos = new ObjectOutputStream(new FileOutputStream("person.object")); oos.writeObject(new Person("liu", 30, "kr"));
oos.writeObject(new Person2("liu", "kr", "kr2"));
oos.writeObject(new Person3(10, 30, 50)); oos.close();
} private static void readObj()throws Exception
{
ObjectInputStream ois = new ObjectInputStream(new FileInputStream("person.object"));
System.out.println(ois.readObject());
System.out.println(ois.readObject());
System.out.println(ois.readObject()); ois.close();
}
}
package packa; import java.io.*; class Person implements Serializable
{
public static final long serialVersionUID = 44L; String name;
transient int age;
static String country = "cn"; Person(String name, int age, String country)
{
this.name = name;
this.age = age;
this.country = country;
} public String toString()
{
return name + " " + age + " " + country;
} }
class Person2 implements Serializable
{
public static final long serialVersionUID = 45L; String name;
String country;
String country2; Person2(String name, String country, String country2)
{
this.name = name;
this.country = country;
this.country2 = country2;
} public String toString()
{
return name + " " + country + " " + country2;
} }
class Person3 implements Serializable
{
public static final long serialVersionUID = 46L; int age;
int age2;
int age3; Person3(int age, int age2, int age3)
{
this.age = age;
this.age2 = age2;
this.age3 = age3;
} public String toString()
{
return age + " " + age2 + " " + age3;
} }