Java操作IO對象流進行數據的讀寫
對象的讀寫使用ObjectInputStream和ObjectOutputStream讀寫對象(序列化與反序列化)。
只有字節流沒有字符流
.類必須實現Serializable接口 給類加個序列化編號,給類定義一個標記,新的修改后的類還可以操作曾經序列化的對象 靜態是不能被序列化的,序列化只能對堆中的進行序列化 ,不能對“方法區”中的進行序列化 不需要序列化的字段前加 transient小例子:
先創建一個Dog對象并序列化:
package com.uwo9.test03; import java.io.Serializable; public class Dog implements Serializable {private static final long serialVersionUID = 2809685095868158625L;String name;String color;}
再創建一個Student對象并序列化:
package com.uwo9.test03; import java.io.Serializable; public class Student implements Serializable {private static final long serialVersionUID = 9078616504949971001L;static public String schoolName;private transient String name;private transient int age;private double score;private Dog dog;public Student() {super();}public Student(String name, int age, double score, Dog dog) {super();this.name = name;this.age = age;this.score = score;this.dog = dog;}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 double getScore() {return score;}public void setScore(double score) {this.score = score;}@Overridepublic String toString() {return 'Student [name=' + name + ', age=' + age + ', score=' + score + ']';} }
將數據寫入對象流并存入文件
package com.uwo9.test03; import java.io.File;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.IOException;import java.io.ObjectOutputStream;import java.util.ArrayList;import java.util.Collections; public class Test01 { public static void main(String[] args) {Dog dog = new Dog();dog.name = '大黃';dog.color = 'Yellow';Student student1 = new Student('學生1', 18, 99,dog);Student student2 = new Student('學生2', 19, 99,dog);Student student3 = new Student('學生3', 20, 99,dog);Student.schoolName = '某某大學';File file = new File('E:/Temp/Test1.txt');ObjectOutputStream oos = null;try {oos = new ObjectOutputStream(new FileOutputStream(file));//oos.writeObject(student);ArrayList<Student> arrayList = new ArrayList<>();Collections.addAll(arrayList, student1,student2,student3);oos.writeObject(arrayList);} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();}finally {try {oos.close();} catch (IOException e) {e.printStackTrace();}}} }
從指定文件中讀取對象
package com.uwo9.test03; import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.IOException;import java.io.ObjectInputStream;import java.util.ArrayList; public class Test02 { public static void main(String[] args) {// 從指定的文件中讀取對象File file = new File('E:/Temp/Test1.txt');ObjectInputStream ois=null;try {ois = new ObjectInputStream(new FileInputStream(file));// 讀取對象// Student stu = (Student)ois.readObject();// System.out.println('讀取到的數據為:'+stu);@SuppressWarnings('unchecked')ArrayList<Student> arrayList = (ArrayList<Student>) ois.readObject();for (Student student : arrayList) {System.out.println(student);}} catch (FileNotFoundException e) {e.printStackTrace();} catch (IOException e) {e.printStackTrace();} catch (ClassNotFoundException e) {e.printStackTrace();}finally {try {ois.close();} catch (IOException e) {e.printStackTrace();}} } }
到此這篇關于Java操作IO對象流進行數據的讀寫的文章就介紹到這了,更多相關Java IO流進行數據的讀寫內容請搜索好吧啦網以前的文章或繼續瀏覽下面的相關文章希望大家以后多多支持好吧啦網!
相關文章:
