--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/main/java/de/mpiwg/gazetteer/bo/LGTopic.java	Thu Dec 17 13:44:08 2015 +0100
@@ -0,0 +1,227 @@
+package de.mpiwg.gazetteer.bo;
+
+import java.io.Serializable;
+import java.sql.SQLException;
+import java.util.ArrayList;
+import java.util.List;
+
+import javax.persistence.Column;
+import javax.persistence.Entity;
+import javax.persistence.Inheritance;
+import javax.persistence.InheritanceType;
+import javax.persistence.Table;
+import javax.persistence.Transient;
+
+import org.json.JSONArray;
+
+import cl.maps.duplex.DuplexKey;
+import de.mpiwg.gazetteer.dataverse.DataverseUtils;
+import de.mpiwg.gazetteer.db.DBBook;
+import de.mpiwg.gazetteer.db.DBSection;
+import de.mpiwg.gazetteer.utils.DBService;
+import de.mpiwg.gazetteer.utils.DataProvider;
+
+
+@Entity
+@Table(name="Topic")
+@Inheritance(strategy=InheritanceType.TABLE_PER_CLASS)
+public class LGTopic extends DBEntry implements Cloneable, Serializable {
+	private static final long serialVersionUID = 7805209462045170778L;
+
+	@Column(name="userId")
+	private Long userId;
+	
+	@Column(name="contributors")
+	private String contributors = "[]";
+	
+	@Column(name="nameEn")
+	private String nameEn;
+	
+	@Column(name="nameCh")
+	private String nameCh;
+	
+	@Column(name="namePinyin")
+	private String namePinyin;
+	
+	@Column(name="description")
+	private String description;
+
+	
+	@Transient
+	private List<Long> contributorsList;
+	
+
+	@Transient
+	private boolean transientDataLoaded = false;
+	
+	
+	
+	public boolean isEmpty() {
+		if (nameEn.equals("") || nameCh.equals("") || namePinyin.equals("") ) {
+			return true;
+		} else {
+			return false;
+		}
+	}
+
+	
+	
+	
+	public boolean isTransientDataLoaded() {
+		return transientDataLoaded;
+	}
+
+
+
+	public Object clone() throws CloneNotSupportedException {
+		 LGTopic clone = (LGTopic)super.clone();
+		 clone.setContributorsList(new ArrayList<Long>(clone.getContributorsList()));
+		 
+		 return clone;
+	}
+	 
+	 
+	
+	public boolean hasContributor(Long userId){
+		for(Long id : getContributorsList()){
+			if(id.equals(userId)){
+				return true;
+			}
+		}
+		return false;
+	}
+	
+	public List<Long> getContributorsList(){
+		if(contributorsList == null){
+			reloadContributorsList();
+		}
+		return contributorsList;
+	}
+	
+	public List<String> getContributorsNameList(){
+		List<String> list = new ArrayList<String>();
+		for(Long userId : getContributorsList()){
+			list.add(DataverseUtils.getUsername(userId));
+		}
+		return list;
+	}
+	
+	public String getUsername(){
+		if(this.userId != null){
+			return DataverseUtils.getUsername(this.userId);
+		}
+		return null;
+	}
+	
+	private void reloadContributorsList(){
+		this.contributorsList = new ArrayList<Long>();
+		try {
+			JSONArray array = new JSONArray(this.contributors);
+			for(int i=0; i<array.length(); i++){
+				this.contributorsList.add(array.getLong(i));
+			}
+		} catch (Exception e) {
+			e.printStackTrace();
+		}
+	}
+	
+	public void addContributor(Long userId){
+		if(!getContributorsList().contains(userId)){
+			getContributorsList().add(userId);
+		}
+		upgradeContributors();
+	}
+	
+	public void removeContributor(Long userId){
+		if(getContributorsList().contains(userId)){
+			getContributorsList().remove(userId);
+			this.upgradeContributors();
+		}
+	}
+	
+	public void upgradeContributors(){
+		JSONArray array = new JSONArray(getContributorsList());
+		this.contributors = array.toString();
+	}
+	
+	
+	public Long getUserId() {
+		return userId;
+	}
+
+	public void setUserId(Long userId) {
+		this.userId = userId;
+	}
+
+	public String getContributors() {
+		return contributors;
+	}
+
+	public void setContributors(String contributors) {
+		this.contributors = contributors;
+	}
+
+	
+	public String getNameEn() {
+		return nameEn;
+	}
+
+
+	public void setNameEn(String nameEn) {
+		this.nameEn = nameEn;
+	}
+
+
+	public String getNameCh() {
+		return nameCh;
+	}
+
+
+	public void setNameCh(String nameCh) {
+		this.nameCh = nameCh;
+	}
+
+
+	public String getNamePinyin() {
+		return namePinyin;
+	}
+
+
+	public void setNamePinyin(String namePinyin) {
+		this.namePinyin = namePinyin;
+	}
+
+
+	public String getDescription() {
+		return description;
+	}
+
+
+
+	public void setDescription(String description) {
+		this.description = description;
+	}
+
+
+
+	public void setContributorsList(List<Long> contributorsList) {
+		this.contributorsList = contributorsList;
+	}
+
+
+	public void setTransientDataLoaded(boolean transientDataLoaded) {
+		this.transientDataLoaded = transientDataLoaded;
+	}
+	
+	public DuplexKey<Long, Long> getKey(){
+		return new DuplexKey<Long, Long>(this.userId, this.id);
+	}
+	
+
+	@Override
+	public String toString(){
+		return "LGTopic[nameEn=" + nameEn + ", nameCh=" + nameCh + ", namePinyin=" + namePinyin + "]";
+	}
+
+	
+}