tools.ResultSetAdapter.java Source code

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Here is the source code for tools.ResultSetAdapter.java

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/*
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 */
package tools;

/**
 *
 * @author nilay jha
 */
import java.io.*;
import java.sql.*;
import com.google.gson.*;
import com.google.gson.stream.*;

public class ResultSetAdapter extends TypeAdapter<ResultSet> {
    public static class NotImplemented extends RuntimeException {
    }

    private static final Gson gson = new Gson();

    @Override
    public ResultSet read(JsonReader reader) throws IOException {
        throw new NotImplemented();
    }

    @Override
    public void write(JsonWriter writer, ResultSet rs) throws IOException {
        try {
            ResultSetMetaData meta = rs.getMetaData();
            int cc = meta.getColumnCount();

            writer.beginArray();
            while (rs.next()) {
                writer.beginObject();
                for (int i = 1; i <= cc; ++i) {
                    writer.name(meta.getColumnName(i));
                    Class<?> type = Class.forName(meta.getColumnClassName(i));
                    gson.toJson(rs.getObject(i), type, writer);
                    //writer.value(rs.getString(i));
                }
                writer.endObject();
            }
            writer.endArray();

        } catch (SQLException | ClassNotFoundException e) {
            throw new RuntimeException(e.getClass().getName(), e);
        }
    }
}

//depricated code
/*
public  JsonObject convertResultSetIntoJSON(ResultSet resultSet) throws Exception {
    JsonArray jsonArray = new JsonArray();
    while (resultSet.next()) {
        int total_rows = resultSet.getMetaData().getColumnCount();
        JsonObject obj = new JsonObject();
        for (int i = 0; i < total_rows; i++) {
            String columnName = resultSet.getMetaData().getColumnLabel(i + 1).toLowerCase();
            Object columnValue = resultSet.getObject(i + 1);
            // if value in DB is null, then we set it to default value
            if (columnValue == null){
                columnValue = "null";
            }
            /*
            Next if block is a hack. In case when in db we have values like price and price1 there's a bug in jdbc - 
            both this names are getting stored as price in ResulSet. Therefore when we store second column value,
            we overwrite original value of price. To avoid that, i simply add 1 to be consistent with DB.
            // 
            if (obj.has(columnName)){
                columnName += "1";
            }
            obj.add(columnName, (JsonElement) columnValue);
        }
        jsonArray.add(obj);
            
    }
     JsonObject obj1 = new JsonObject();
        obj1.add("data",jsonArray);
           
    return obj1;
}*/