Access data from a postgres db rather than the example glom file.

[online-glom:gwt-glom.git] / src / main / java / org / glom / web / server / LibGlomServiceImpl.java

package org.glom.web.server;

import java.beans.PropertyVetoException;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;

import org.glom.libglom.Document;
import org.glom.libglom.Field;
import org.glom.libglom.Glom;
import org.glom.libglom.LayoutFieldVector;
import org.glom.libglom.LayoutGroupVector;
import org.glom.libglom.LayoutItem;
import org.glom.libglom.LayoutItemVector;
import org.glom.libglom.LayoutItem_Field;
import org.glom.libglom.StringVector;
import org.glom.web.client.GlomDocument;
import org.glom.web.client.GlomTable;
import org.glom.web.client.LibGlomService;

import com.google.gwt.user.server.rpc.RemoteServiceServlet;
import com.mchange.v2.c3p0.ComboPooledDataSource;
import com.mchange.v2.c3p0.DataSources;

@SuppressWarnings("serial")
public class LibGlomServiceImpl extends RemoteServiceServlet implements LibGlomService {
        private Document document;
        ComboPooledDataSource cpds;

        // Called only when the servlet is stopped (the servlet container is stopped or restarted)
        public LibGlomServiceImpl() {
                Glom.libglom_init();
                document = new Document();
                // TODO hardcoded for now, need to figure out something for this
                document.set_file_uri("file:///home/ben/music-collection.glom");
                int error = 0;
                @SuppressWarnings("unused")
                boolean retval = document.load(error);
                // TODO handle error condition (also below)

                cpds = new ComboPooledDataSource();
                // load the jdbc driver
                try {
                        cpds.setDriverClass("org.postgresql.Driver");
                } catch (PropertyVetoException e) {
                        // TODO log error, fatal error can't continue, user can be nofified when db access doesn't work
                        e.printStackTrace();
                }

                cpds.setJdbcUrl("jdbc:postgresql://" + document.get_connection_server() + "/"
                                + document.get_connection_database());
                // TODO figure out something for db user name and password
                cpds.setUser("ben");
                cpds.setPassword("ChangeMe"); // of course it's not the password I'm using on my server
        }

        /* FIXME I think Swig is generating long on 64-bit machines and int on 32-bit machines - need to keep this constant
         * http://stackoverflow.com/questions /1590831/safely-casting-long-to-int-in-java */
        public static int safeLongToInt(long l) {
                if (l < Integer.MIN_VALUE || l > Integer.MAX_VALUE) {
                        throw new IllegalArgumentException(l + " cannot be cast to int without changing its value.");
                }
                return (int) l;
        }

        public GlomDocument getGlomDocument() {
                GlomDocument glomDocument = new GlomDocument();

                // set visible title
                glomDocument.setTitle(document.get_database_title());

                // set array of GlomTables and the default table index
                StringVector tableNames = document.get_table_names();
                GlomTable[] tables = new GlomTable[safeLongToInt(tableNames.size())];
                for (int i = 0; i < tableNames.size(); i++) {
                        String tableName = tableNames.get(i);
                        GlomTable glomTable = new GlomTable();
                        glomTable.setName(tableName);
                        glomTable.setTitle(document.get_table_title(tableName));
                        tables[i] = glomTable;
                        if (tableName.equals(document.get_default_table())) {
                                glomDocument.setDefaultTableIndex(i);
                        }
                }
                glomDocument.setTables(tables);
                return glomDocument;

        }

        public String[] getLayoutListHeaders(String table) {
                LayoutGroupVector layoutList = document.get_data_layout_groups("list", table);
                LayoutItemVector layoutItems = layoutList.get(0).get_items();
                String[] headers = new String[safeLongToInt(layoutItems.size())];
                for (int i = 0; i < layoutItems.size(); i++) {
                        headers[i] = layoutItems.get(i).get_title_or_name();
                }
                return headers;
        }

        public ArrayList<String[]> getTableData(int start, int length, String table) {
                LayoutGroupVector layoutList = document.get_data_layout_groups("list", table);
                LayoutItemVector layoutItems = layoutList.get(0).get_items();

                LayoutFieldVector layoutFields = new LayoutFieldVector();
                for (int i = 0; i < layoutItems.size(); i++) {
                        LayoutItem item = layoutItems.get(i);
                        LayoutItem_Field field = LayoutItem_Field.cast_dynamic(item);
                        if (field != null) {
                                layoutFields.add(field);
                                Field details = field.get_full_field_details();
                                if (details != null && details.get_primary_key()) {
                                        // TODO implement this for sort order, will need to sort out swig support for std::list in Java
                                        // C++ code to port to Java:
                                        // sort_clause.push_back(Glom::type_pair_sort_field(field, true));
                                }
                        }
                }

                ArrayList<String[]> rowsList = new ArrayList<String[]>();
                try {
                        Connection conn = cpds.getConnection();
                        Statement st = conn.createStatement();

                        String query = Glom.build_sql_select_simple(table, layoutFields);
                        ResultSet rs = st.executeQuery(query);

                        while (rs.next()) {
                                String[] rowArray = new String[safeLongToInt(layoutItems.size())];
                                for (int i = 0; i < layoutItems.size(); i++) {
                                        rowArray[i] = rs.getString(i + 1);
                                }
                                rowsList.add(rowArray);
                        }

                        rs.close();
                        st.close();
                } catch (SQLException e) {
                        // TODO: log error, notify user of problem
                        e.printStackTrace();
                }

                return rowsList;
        }

        // Called only when the servlet is stopped (the servlet container is stopped or restarted)
        public void destroy() {
                Glom.libglom_deinit();
                try {
                        DataSources.destroy(cpds);
                } catch (SQLException e) {
                        // TODO log error, don't need to notify user because this is a clean up method
                        e.printStackTrace();
                }
        }

}