Java db4o-检索对象时的奇怪字符
我只想将一个学生存储在db4o数据库中,但当我想检索所有学生时,它的输出如下:Java db4o-检索对象时的奇怪字符,java,database,db4o,Java,Database,Db4o,我只想将一个学生存储在db4o数据库中,但当我想检索所有学生时,它的输出如下: import java.io.File; import com.db4o.Db4o; import com.db4o.Db4oEmbedded; import com.db4o.ObjectContainer; import com.db4o.ObjectSet; import com.db4o.query.Query; public class Student { private String name; p
import java.io.File;
import com.db4o.Db4o;
import com.db4o.Db4oEmbedded;
import com.db4o.ObjectContainer;
import com.db4o.ObjectSet;
import com.db4o.query.Query;
public class Student {
private String name;
public AlumnoBDOO(String name){
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public static void main(String[] args) {
ObjectContainer bd = Db4oEmbedded.openFile("students.db4o");
try {
Student s1 = new Student("Carl");
bd.store(s1)
showStudents(bd);
} catch (Exception e) {
e.printStackTrace();
} finally {
bd.close();
}
}
public static void showResult(ObjectSet rs){
System.out.println("Retrieved "+rs.size()+" objects");
while(rs.hasNext()){
System.out.println(rs.next());
}
}
public static void showStudents(ObjectContainer bd){
Query query = bd.query();
query.constrain(Student.class);
query.descend("name");
ObjectSet rs = query.execute();
showResult(rs);
}
}
我正在使用EclipseJuno和DB40V.8.0,我已经将其添加为外部jar。
为什么我得到的是那些奇怪的字符而不是“Carl”?这不是weired,而是该方法的默认实现。要获得有意义的完整信息,您应该在学生课堂上覆盖此方法。哦,谢谢。我已经尝试过toString方法,但直接在打印行中,没有将其作为方法实现:)
Student@61070a02