com.bedatadriven.rebar.sync.server.JpaUpdateBuilder.java Source code

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Here is the source code for com.bedatadriven.rebar.sync.server.JpaUpdateBuilder.java

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/*
 * Copyright 2009-2010 BeDataDriven (alex@bedatadriven.com)
 *
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.bedatadriven.rebar.sync.server;

import com.bedatadriven.rebar.persistence.mapping.EntityMapping;
import com.bedatadriven.rebar.persistence.mapping.PropertyMapping;
import com.bedatadriven.rebar.persistence.mapping.UnitMapping;
import org.json.JSONException;
import org.json.JSONStringer;

import java.util.List;

/**
 * Generates a jsonnified BulkOperation object that can be sent
 * to and executed by the client against the local jdbc database
 *
 * @author Alex Bertram
 */
public class JpaUpdateBuilder {

    private JSONStringer json;
    private UnitMapping context;

    public JpaUpdateBuilder() {
        json = new JSONStringer();
        try {
            json.array();
        } catch (JSONException e) {
            throw new RuntimeException(e);
        }
        context = new UnitMapping();
    }

    public void executeStatement(String sql) throws JSONException {
        json.object();
        json.key("statement");
        json.value(sql);
        json.endObject();
    }

    public void beginPreparedStatement(String sql) throws JSONException {
        json.object();
        json.key("statement");
        json.value(sql);
        json.key("executions");
        json.array();
    }

    public void addExecution(Object... parameters) throws JSONException {
        json.array();
        for (Object p : parameters) {
            json.value(p);
        }
        json.endArray();
    }

    public void finishPreparedStatement() throws JSONException {
        json.endArray();
        json.endObject();
    }

    public void createTableIfNotExists(Class entityClass) throws JSONException {
        EntityMapping mapping = context.getMapping(entityClass);

        json.object();

        json.key("statement");
        json.value(mapping.getCreateTableStatement());

        json.endObject();
    }

    public void deleteAll(Class entityClass) throws JSONException {
        EntityMapping mapping = context.getMapping(entityClass);

        json.object();

        json.key("statement");
        json.value("delete from " + mapping.getTableName());

        json.endObject();
    }

    public <T> void insert(Class<T> entityClass, List<T> entities) throws JSONException {
        insert("", entityClass, entities);
    }

    public <T> void insert(String conflictClause, Class<T> entityClass, List<T> entities) throws JSONException {

        if (entities.size() == 0) {
            return; // nothing to do
        }
        // get/create the mapping for this entity
        EntityMapping mapping = context.getMapping(entityClass);

        // start a new BulkOperation object
        json.object();

        // first build the insert statement
        json.key("statement");
        json.value(mapping.getInsertStatement(conflictClause));

        json.key("executions");
        json.array();

        // loop through each of the entities in the list
        for (T entity : entities) {

            json.array();

            // write the other columns
            for (PropertyMapping property : mapping.getProperties()) {
                if (property.isInsertable()) {
                    property.writeColumnValues(json, entity);
                }
            }
            json.endArray();
        }

        json.endArray(); // end our batches
        json.endObject(); //end the BulkOperation object
    }

    public <T> void update(Class<T> entityClass, List<T> entities) throws JSONException {

        if (entities.size() == 0) {
            return; // nothing to do
        }
        // get/create the mapping for this entity
        EntityMapping mapping = context.getMapping(entityClass);

        // start a new BulkOperation object
        json.object();

        // first build the insert statement
        json.key("statement");
        json.value(mapping.getUpdateStatement());

        json.key("executions");
        json.array();

        // loop through each of the entities in the list
        for (T entity : entities) {

            json.array();

            // write the columns to update
            for (PropertyMapping property : mapping.getProperties()) {
                if (property.isUpdatable()) {
                    property.writeColumnValues(json, entity);
                }
            }

            // write the ids used to select the row
            mapping.getId().writeColumnValues(json, entity);

            json.endArray();
        }

        json.endArray(); // end our batches
        json.endObject(); //end the BulkOperation object
    }

    public <T> void delete(Class<T> entityClass, List<T> entities) throws JSONException {

        if (entities.size() == 0) {
            return; // nothing to do
        }
        // get/create the mapping for this entity
        EntityMapping mapping = context.getMapping(entityClass);

        // start a new BulkOperation object
        json.object();

        // first build the insert statement
        json.key("statement");
        json.value(mapping.getDeleteStatement());

        json.key("executions");
        json.array();

        // loop through each of the entities in the list
        for (T entity : entities) {

            json.array();

            mapping.getId().writeColumnValues(json, entity);

            json.endArray();
        }

        json.endArray(); // end our batches
        json.endObject(); //end the BulkOperation object
    }

    public String asJson() throws JSONException {
        json.endArray();
        return json.toString();
    }

}