默认格式
复制代码 代码如下:
public class MyClass implements Serializable{
...}
序列化：
复制代码 代码如下:
ObjectOutputStream output = new ObjectOutputStream(new FileOutputStream(outputPath));
output.writeObject(myObject);
反序列化：
复制代码 代码如下:
ObjectInputStream input = new ObjectInputStream(new FileInputStream(inputPath));
return (MyClass)input.readObject();
JSON格式
使用jackson包。jackson是一个效率非常高的Java JSON包。文档和下载见官网。
序列化
复制代码 代码如下:
ObjectMapper mapper = new ObjectMapper();
mapper.writeValue(new File(outputPath), myObject);
反序列化：
复制代码 代码如下:
return mapper.readValue(new File(outputPath), MyClass.class);
完整测试代码
复制代码 代码如下:
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.ObjectInputStream;
import java.io.ObjectOutputStream;
import java.io.Serializable;
import java.util.ArrayList;
import com.fasterxml.jackson.core.JsonGenerationException;
import com.fasterxml.jackson.core.JsonParseException;
import com.fasterxml.jackson.databind.JsonMappingException;
import com.fasterxml.jackson.databind.ObjectMapper;
public class Zoo implements Serializable {
private static final long serialVersionUID = 1L;
private static ObjectMapper mapper = new ObjectMapper();
public static int maxAnimalCount;
public ArrayList<String> animals;
public Zoo() {
animals = new ArrayList<String>();
}
public static void setMax(int max){
maxAnimalCount = max;
}
/**
* Add an animal to animals Array.
* @param animalName
*/
public void addAnimal(String animalName){
if (animals.size() < maxAnimalCount)
animals.add(animalName);
}
@Override
public String toString(){
return "Zoo: n animals: " + animals.toString() +
"n maxAnimalCount: " + maxAnimalCount + "n";
}
/**
* Output standard serialization to file at logPath.
* @param logPath
*/
public void serializeToLog(String logPath) {
ObjectOutputStream output = null;
try
{
output = new ObjectOutputStream(
new FileOutputStream(logPath));
output.writeObject(this);
} catch(Exception e) {
e.printStackTrace();
} finally {
try {
output.close();
} catch (IOException e) {
e.printStackTrace();
}
}
}
/**
* Output JSON serialization(using jackson) to file at logPath.
* @param logPath
*/
public void serializeJSONToLog(String logPath){
try {
mapper.writeValue(new File(logPath), this);
} catch (JsonGenerationException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
}
/**
* Standard deserialize a Zoo instance from file at logPath.
* @param logPath
* @return deserialized zoo instance
*/
public static Zoo deserializeFromLog(String logPath) {
ObjectInputStream input = null;
try
{
input =new ObjectInputStream(
new FileInputStream(logPath));
return (Zoo)input.readObject();
} catch(Exception e) {
e.printStackTrace();
} finally {
try {
input.close();
} catch (IOException e) {
e.printStackTrace();
}
}
return null;
}
/**
* JSON deserialize a Zoo instance from file at logPath.
* @param logPath
* @return JSON deserialized zoo instance
*/
public static Zoo deserializeJSONFromLog(String logPath){
try {
return mapper.readValue(new File(logPath), Zoo.class);
} catch (JsonParseException e) {
e.printStackTrace();
} catch (JsonMappingException e) {
e.printStackTrace();
} catch (IOException e) {
e.printStackTrace();
}
return null;
}
}
class ZooSerializeTest {
public static void main(String[] args) {
Zoo zoo1 = new Zoo();
Zoo.setMax(100);
zoo1.addAnimal("hamster");
zoo1.addAnimal("sheep");
zoo1.serializeToLog("zoo1.log");
Zoo zoo2 = new Zoo();
Zoo.setMax(200);
zoo2.addAnimal("tiger");
zoo2.serializeToLog("zoo2.log");
Zoo.setMax(300);
//Deserialization
zoo1 = Zoo.deserializeFromLog("zoo1.log");
zoo2 = Zoo.deserializeFromLog("zoo2.log");
System.out.println("zoo1: n" + zoo1);
System.out.println("zoo2: n" + zoo2);
//Serialize to JSON
zoo1.serializeJSONToLog("zoo1.json");
zoo1 = Zoo.deserializeJSONFromLog("zoo1.json");
System.out.println("zoo1 from json: n" + zoo1);
}
}