Use your own database table from frontend ( GWT )

Methods

The class OKMDatabaseMetadataService has the interface definition to access metadata services.

Sample

Register database metadata table definition

Go to Administration > Tools > Database query and execute the SQL: 

INSERT INTO OKM_DB_METADATA_TYPE (DMT_TABLE, DMT_REAL_COLUMN, DMT_TYPE, DMT_VIRTUAL_COLUMN) VALUES ('security', 'col00', 'text', 'uuid_id');
INSERT INTO OKM_DB_METADATA_TYPE (DMT_TABLE, DMT_REAL_COLUMN, DMT_TYPE, DMT_VIRTUAL_COLUMN) VALUES ('security', 'col01', 'text', 'type');
INSERT INTO OKM_DB_METADATA_TYPE (DMT_TABLE, DMT_REAL_COLUMN, DMT_TYPE, DMT_VIRTUAL_COLUMN) VALUES ('security', 'col02', 'text', 'name');

Java classes

File GWTExtendedSecurity.java:

public class GWTExtendedSecurity extends DatabaseMetadataCommon implements IsSerializable {
    public static final String TYPE_USER = "user";
    public static final String TYPE_ROLE = "role";
 
    // Metadata Virtual Name mapping 
    public static final String MV_TABLE_NAME = "security";
    public static final String MV_COLUMN_NAME_UUID = "uuid_id";
    public static final String MV_COLUMN_NAME_TYPE = "type";
    public static final String MV_COLUMN_NAME_NAME = "name";
 
    private String uuid;
    private String type;
    private String name;
 
    @Override
    public void loadFromMap(Map<String, String> map) {
        super.loadFromMap(map);
 
        if (map.containsKey(MV_COLUMN_NAME_UUID)) {
            setUuid(map.get(MV_COLUMN_NAME_UUID));
        }
 
        if (map.containsKey(MV_COLUMN_NAME_TYPE)) {
            setType(map.get(MV_COLUMN_NAME_TYPE));
        }
 
        if (map.containsKey(MV_COLUMN_NAME_NAME)) {
            setName(map.get(MV_COLUMN_NAME_NAME));
        }
    }
 
    @Override
    public Map<String, String> restoreToMap() {
        Map<String,String> map = super.restoreToMap();
 
        if (uuid != null) {
            map.put(MV_COLUMN_NAME_UUID, getUuid());
        }
 
        if (type != null) {
            map.put(MV_COLUMN_NAME_TYPE, getType());
        }
 
        if (name != null) {
            map.put(MV_COLUMN_NAME_NAME, getName());
        }
 
        return map;
    }
 
    public String getUuid() {
        return uuid;
    }
 
    public void setUuid(String uuid) {
        this.uuid = uuid;
    }
 
    public String getType() {
        return type;
    }
 
    public void setType(String type) {
        this.type = type;
    }
 
    public String getName() {
        return name;
    }
 
    public void setName(String name) {
        this.name = name;
    }
}

File Example.java:

public class Example {
    private final OKMDatabaseMetadataServiceAsync metadataService = (OKMDatabaseMetadataServiceAsync) GWT.create(OKMDatabaseMetadataService.class);
 
    public void test() {
        // get sequence
        metadataService.getNextSequenceValue("table_name", "col_name" , new AsyncCallback<Double>() {
            @Override
            public void onSuccess(Double result) {
                int value = result.intValue();
            }
 
            @Override
            public void onFailure(Throwable caught) {
            }
        });
 
        // create value
        final GWTExtendedSecurity security = new GWTExtendedSecurity();
        security.setUuid("some uuid");
        security.setName("some name");
        security.setType(GWTExtendedSecurity.TYPE_ROLE);
        security.setRealTable(GWTExtendedSecurity.MV_TABLE_NAME);
        metadataService.createValue(security.restoreToMap(), new AsyncCallback<Double>() {
            @Override
            public void onSuccess(Double result) {
                // created
            }
 
            @Override
            public void onFailure(Throwable caught) {
            }
        });
 
        // Execute query
	String filter = "$" + GWTExtendedSecurity.MV_COLUMN_NAME_UUID + "='some uuid'";
        metadataService.executeValueQuery(GWTExtendedSecurity.MV_TABLE_NAME, filter, "", new AsyncCallback<List<Map<String,String>>>() {
            @Override
            public void onSuccess(List<Map<String, String>> result) {
                if (result.size() > 0) {
                    GWTExtendedSecurity security = new GWTExtendedSecurity();
                    security.loadFromMap(result.get(0));
                }
            }
 
            @Override
            public void onFailure(Throwable caught) {
                GeneralComunicator.showError("executeValueQuery", caught);
            }
        });
 
        // Update value
        security.setName("some name changed");
        metadataService.updateValue(security.restoreToMap(), new AsyncCallback<Object>() {
            @Override
            public void onSuccess(Object result) {
            }
 
            @Override
            public void onFailure(Throwable caught) {
            }
        });
 
        // Delete value
        metadataService.deleteValue(security.restoreToMap(), new AsyncCallback<Object>() {
            @Override
            public void onSuccess(Object result) {
            }
 
            @Override
            public void onFailure(Throwable caught) {
            }
        });
    }
}

Advanced

Also can be done joins between tables for it should be used method executeMultiValueQuery:

List<String> tables = new ArrayList<String>();
tables.add(GWTCountry.MV_TABLE_NAME);
tables.add(GWTState.MV_TABLE_NAME);
 
String query = "from DatabaseMetadataValue dmv1, DatabaseMetadataValue dmv2 ";
query += "where dmv1.table='" + GWTCountry.MV_TABLE_NAME + "' ";
query += "and dmv2.table='" + GWTState.MV_TABLE_NAME + "' ";
query += "and dmv1.$" + GWTCountry.MV_COLUMN_COUNTRY_NAME + "='SPAIN' ";
query += "and dmv1.$" + GWTCountry.MV_COLUMN_COUNTRY_NAME + "=" + "dmv2.$" + GWTState.MV_COLUMN_COUNTRY_NAME;
 
metadataService.executeMultiValueQuery(tables, query, new AsyncCallback<List<List<Map<String,String>>>>() {
    @Override
    public void onSuccess(List<List<Map<String, String>>> result) {
        if (!result.isEmpty()) {
            List<Map<String, String>> dmvRow = result.get(0);
 
            if (!dmvRow.isEmpty() && dmvRow.size() == 2) {
                GWTState state = new GWTState();
                state.loadFromMap(dmvRow.get(1));
            }
        } 
    }
 
    @Override
    public void onFailure(Throwable caught) {
    }
});