public class ArrayList<E> extends AbstractList<E>
    implements List<E>, RandomAccess, Cloneable, java.io.Serializable
{
  private static final long serialVersionUID = 8683452581122892189L;

  transient Object[] elementData; // non-private to simplify nested class access

  private int size;
}

package com.hollis;
import java.io.Serializable;
import java.util.Date;

/**
 * Created by hollis on 16/2/2.
 */
public class User implements Serializable{
  private String name;
  private int age;
  private Date birthday;
  private transient String gender;
  private static final long serialVersionUID = -6849794470754667710L;

  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 Date getBirthday() {
    return birthday;
  }

  public void setBirthday(Date birthday) {
    this.birthday = birthday;
  }

  public String getGender() {
    return gender;
  }

  public void setGender(String gender) {
    this.gender = gender;
  }

  @Override
  public String toString() {
    return "User{" +
        "name='" + name + '\'' +
        ", age=" + age +
        ", gender=" + gender +
        ", birthday=" + birthday +
        '}';
  }
}

package com.hollis;
import org.apache.commons.io.FileUtils;
import org.apache.commons.io.IOUtils;
import java.io.*;
import java.util.Date;

/**
 * Created by hollis on 16/2/2.
 */
public class SerializableDemo {

  public static void main(String[] args) {
    //Initializes The Object
    User user = new User();
    user.setName("hollis");
    user.setGender("male");
    user.setAge(23);
    user.setBirthday(new Date());
    System.out.println(user);

    //Write Obj to File
    ObjectOutputStream oos = null;
    try {
      oos = new ObjectOutputStream(new FileOutputStream("tempFile"));
      oos.writeObject(user);
    } catch (IOException e) {
      e.printStackTrace();
    } finally {
      IOUtils.closeQuietly(oos);
    }

    //Read Obj from File
    File file = new File("tempFile");
    ObjectInputStream ois = null;
    try {
      ois = new ObjectInputStream(new FileInputStream(file));
      User newUser = (User) ois.readObject();
      System.out.println(newUser);
    } catch (IOException e) {
      e.printStackTrace();
    } catch (ClassNotFoundException e) {
      e.printStackTrace();
    } finally {
      IOUtils.closeQuietly(ois);
      try {
        FileUtils.forceDelete(file);
      } catch (IOException e) {
        e.printStackTrace();
      }
    }

  }
}
//output 
//User{name='hollis', age=23, gender=male, birthday=Tue Feb 02 17:37:38 CST 2016}
//User{name='hollis', age=23, gender=null, birthday=Tue Feb 02 17:37:38 CST 2016}

public class ArrayList<E> extends AbstractList<E>
    implements List<E>, RandomAccess, Cloneable, java.io.Serializable
{
  private static final long serialVersionUID = 8683452581122892189L;
  transient Object[] elementData; // non-private to simplify nested class access
  private int size;
}

public static void main(String[] args) throws IOException, ClassNotFoundException {
    List<String> stringList = new ArrayList<String>();
    stringList.add("hello");
    stringList.add("world");
    stringList.add("hollis");
    stringList.add("chuang");
    System.out.println("init StringList" + stringList);
    ObjectOutputStream objectOutputStream = new ObjectOutputStream(new FileOutputStream("stringlist"));
    objectOutputStream.writeObject(stringList);

    IOUtils.close(objectOutputStream);
    File file = new File("stringlist");
    ObjectInputStream objectInputStream = new ObjectInputStream(new FileInputStream(file));
    List<String> newStringList = (List<String>)objectInputStream.readObject();
    IOUtils.close(objectInputStream);
    if(file.exists()){
      file.delete();
    }
    System.out.println("new StringList" + newStringList);
  }
//init StringList[hello, world, hollis, chuang]
//new StringList[hello, world, hollis, chuang]

private void readObject(java.io.ObjectInputStream s)
    throws java.io.IOException, ClassNotFoundException {
    elementData = EMPTY_ELEMENTDATA;

    // Read in size, and any hidden stuff
    s.defaultReadObject();

    // Read in capacity
    s.readInt(); // ignored

    if (size > 0) {
      // be like clone(), allocate array based upon size not capacity
      ensureCapacityInternal(size);

      Object[] a = elementData;
      // Read in all elements in the proper order.
      for (int i=0; i<size; i++) {
        a[i] = s.readObject();
      }
    }
  }

private void writeObject(java.io.ObjectOutputStream s)
    throws java.io.IOException{
    // Write out element count, and any hidden stuff
    int expectedModCount = modCount;
    s.defaultWriteObject();

    // Write out size as capacity for behavioural compatibility with clone()
    s.writeInt(size);

    // Write out all elements in the proper order.
    for (int i=0; i<size; i++) {
      s.writeObject(elementData[i]);
    }

    if (modCount != expectedModCount) {
      throw new ConcurrentModificationException();
    }
  }

void invokeWriteObject(Object obj, ObjectOutputStream out)
    throws IOException, UnsupportedOperationException
  {
    if (writeObjectMethod != null) {
      try {
        writeObjectMethod.invoke(obj, new Object[]{ out });
      } catch (InvocationTargetException ex) {
        Throwable th = ex.getTargetException();
        if (th instanceof IOException) {
          throw (IOException) th;
        } else {
          throwMiscException(th);
        }
      } catch (IllegalAccessException ex) {
        // should not occur, as access checks have been suppressed
        throw new InternalError(ex);
      }
    } else {
      throw new UnsupportedOperationException();
    }
  }

public interface Serializable {
}

if (obj instanceof String) {
        writeString((String) obj, unshared);
      } else if (cl.isArray()) {
        writeArray(obj, desc, unshared);
      } else if (obj instanceof Enum) {
        writeEnum((Enum<?>) obj, desc, unshared);
      } else if (obj instanceof Serializable) {
        writeOrdinaryObject(obj, desc, unshared);
      } else {
        if (extendedDebugInfo) {
          throw new NotSerializableException(
            cl.getName() + "\n" + debugInfoStack.toString());
        } else {
          throw new NotSerializableException(cl.getName());
        }
      }