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package design.persistence;
import com.fasterxml.jackson.annotation.JsonAutoDetect;
import com.fasterxml.jackson.annotation.PropertyAccessor;
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.*;
import com.fasterxml.jackson.databind.module.SimpleModule;
import design.model.Course;
import design.model.Golfer;
import java.io.File;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
public class JSONPersonalDatabase implements PersonalDatabase {
private final Map<String, Golfer> cache;
private final ObjectMapper mapper;
private final File file;
public JSONPersonalDatabase(String filename) {
this.file = new File(filename);
this.cache = new HashMap<>();
this.mapper = new ObjectMapper();
SimpleModule module = new SimpleModule();
module.addDeserializer(Course.class, new CourseIdDeserializer());
module.addSerializer(Course.class, new CourseIdSerializer());
mapper.registerModule(module);
mapper.setVisibility(PropertyAccessor.FIELD, JsonAutoDetect.Visibility.ANY);
mapper.writerWithDefaultPrettyPrinter();
try {
load();
} catch (IOException ex) {
throw new RuntimeException(ex);
}
}
private void load() throws IOException {
Golfer[] data = mapper.readValue(file, Golfer[].class);
cache.clear();
for (Golfer i : data) {
cache.put(i.getUsername(), i);
}
}
private void save() throws IOException {
Golfer[] data = cache.values().toArray(Golfer[]::new);
mapper.writeValue(file, data);
}
@Override
public Golfer[] getGolfers() {
return new Golfer[0];
}
@Override
public Golfer getGolfer(String username) {
return cache.get(username);
}
@Override
public void addGolfer(Golfer golfer) throws IOException {
cache.put(golfer.getUsername(), golfer);
save();
}
@Override
public void removeGolfer(Golfer golfer) throws IOException {
cache.remove(golfer.getUsername());
save();
}
@Override
public void updateGolfer(Golfer golfer) throws IOException {
cache.put(golfer.getUsername(), golfer);
save();
}
private static class CourseIdSerializer extends JsonSerializer<Course> {
@Override
public void serialize(Course course, JsonGenerator gen, SerializerProvider serializers) throws IOException {
gen.writeNumber(course.getId());
}
}
private static class CourseIdDeserializer extends JsonDeserializer<Course> {
MasterDatabase masterDB = MasterDatabase.INSTANCE;
@Override
public Course deserialize(JsonParser p, DeserializationContext context) throws IOException {
int id = p.getValueAsInt();
return masterDB.getCourse(id);
}
}
}
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