サンプル
XmlSerializer.java
import java.beans.XMLDecoder;
import java.beans.XMLEncoder;
import java.io.BufferedInputStream;
import java.io.BufferedOutputStream;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.util.ArrayList;
import java.util.Collections;
import java.util.List;
public class XmlSerializer {
// 実験用
public static void main(String[] args) {
// Case1 : 単一
Person person = new Person("Isabella", 3, true);
String fileName1 = "person.xml";
XmlSerializer.save(fileName1, person);
Person newPerson = XmlSerializer.loadValue(fileName1, Person.class);
// 出力
System.out.println("Case1 : 単一");
System.out.println(newPerson.getName() + "(" + newPerson.getAge() + ") is Woman? : " + newPerson.isWoman());
System.out.println("");
// Case2 : リスト
List<Person> people = new ArrayList<>();
Person person1 = new Person("Ken", 62, true);
people.add(person1);
Person person2 = new Person("Coco", 10, false);
people.add(person2);
String fileName = "people.xml";
XmlSerializer.save(fileName, people);
List<Person> newPeople = XmlSerializer.loadValues(fileName, Person.class);
// 出力
System.out.println("Case2 : リスト");
for (Person newPersonInList : newPeople) {
System.out.println(
newPersonInList.getName() + "(" + newPersonInList.getAge() + ") is Woman? : " + newPersonInList.isWoman());
}
System.out.println("");
// Case3 : 全く別のクラスをロード
List<DummyPerson> newDummyPeople = XmlSerializer.loadValues(fileName, DummyPerson.class);
// 出力
System.out.println("Case3 : 全く別のクラスをロード");
for (DummyPerson newDummyPerson : newDummyPeople) {
System.out.println(newDummyPerson.getName() + "(" + newDummyPerson.getAge() + ")");
}
if (newDummyPeople.isEmpty()) {
System.out.println("Empty");
}
System.out.println("");
System.out.println("Done");
}
// 共通化
public static <T> void save(String fileName, T objectToSave) {
try (XMLEncoder xMLEncoder = new XMLEncoder(new BufferedOutputStream(new FileOutputStream(fileName)));) {
xMLEncoder.writeObject(objectToSave);
} catch (FileNotFoundException e) {
e.printStackTrace();
}
}
public static <T> T loadValue(String fileName, Class<T> clazz) {
Object value = XmlSerializer.load(fileName);
if (value == null || value.getClass() != clazz) {
return null;
}
return clazz.cast(value);
}
@SuppressWarnings("unchecked")
public static <T> List<T> loadValues(String fileName, Class<T> clazz) {
Object value = XmlSerializer.load(fileName);
if (value == null || !(value instanceof List<?>)) {
Collections.emptyList();
}
List<Object> values = (List<Object>) value;
if (values.isEmpty() || !values.get(0).getClass().isAssignableFrom(clazz)) {
return Collections.emptyList();
}
return (List<T>) values;
}
private static Object load(String fileName) {
try (XMLDecoder xMLDecoder = new XMLDecoder(new BufferedInputStream(new FileInputStream(fileName)));) {
return xMLDecoder.readObject();
} catch (FileNotFoundException e) {
e.printStackTrace();
}
return null;
}
}
import java.io.Serializable;
public class Person implements Serializable {
private static final long serialVersionUID = 1L;
private String name;
private int age;
private boolean isWoman;
public Person() {
this(null, -1, false);
}
public Person(String name, int age, boolean isWoman) {
this.name = name;
this.age = age;
this.isWoman = isWoman;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return this.age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isWoman() {
return this.isWoman;
}
public void setWoman(boolean isWoman) {
this.isWoman = isWoman;
}
}
DummyPerson.java
ダミークラス
import java.io.Serializable;
public class Person implements Serializable {
private static final long serialVersionUID = 1L;
private String name;
private int age;
private boolean isWoman;
public Person() {
this(null, -1, false);
}
public Person(String name, int age, boolean isWoman) {
this.name = name;
this.age = age;
this.isWoman = isWoman;
}
public String getName() {
return this.name;
}
public void setName(String name) {
this.name = name;
}
public int getAge() {
return this.age;
}
public void setAge(int age) {
this.age = age;
}
public boolean isWoman() {
return this.isWoman;
}
public void setWoman(boolean isWoman) {
this.isWoman = isWoman;
}
}
出力結果
コンソール画面
Case1 : 単一
Isabella(3) is Woman? : true
Case2 : リスト
Ken(62) is Woman? : true
Coco(10) is Woman? : false
Case3 : 全く別のクラスをロード
Empty
Done
person.xml
<?xml version="1.0" encoding="UTF-8"?>
<java version="1.8.0_144" class="java.beans.XMLDecoder">
<object class="com.sample.xml.Person">
<void property="age">
<int>3</int>
</void>
<void property="name">
<string>Isabella</string>
</void>
<void property="woman">
<boolean>true</boolean>
</void>
</object>
</java>
people.xml
<?xml version="1.0" encoding="UTF-8"?>
<java version="1.8.0_144" class="java.beans.XMLDecoder">
<object class="java.util.ArrayList">
<void method="add">
<object class="com.sample.xml.Person">
<void property="age">
<int>62</int>
</void>
<void property="name">
<string>Ken</string>
</void>
<void property="woman">
<boolean>true</boolean>
</void>
</object>
</void>
<void method="add">
<object class="com.sample.xml.Person">
<void property="age">
<int>10</int>
</void>
<void property="name">
<string>Coco</string>
</void>
</object>
</void>
</object>
</java>
