对电影进行个性化推荐，基于Mahout框架实现的，使用的协同过滤算法+源代码+文档说明

package zjn.dao; import java.sql.Connection; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.util.ArrayList; import java.util.Arrays; import java.util.Collection; import java.util.HashMap; import java.util.List; import java.util.Map; import zjn.model.Movie; import zjn.util.DBUtil; import zjn.util.StringUtil; public class MovieDao { public final static String TABLE_NAME = "movies"; public final static String ID_COLUMN = "id"; public final static String NAME_COLUMN = "name"; public final static String PUBLISHED_YEAR_COLUMN = "published_year"; public final static String TYPE_COLUMN = "type"; public static void insertMovie(Movie movie){ } public static void insertMovies(List<Movie> movies){ Connection conn = DBUtil.getConnection(); PreparedStatement ps = null; String sql = "insert into " + TABLE_NAME + " ( " + ID_COLUMN + ", " + NAME_COLUMN + ", " + TYPE_COLUMN + ") values (?, ?, ?)"; try { conn.setAutoCommit(false); ps = conn.prepareStatement(sql); for (Movie movie : movies) { ps.setInt(1, movie.getId()); ps.setString(2, movie.getName()); ps.setString(3, StringUtil.connectString(movie.getType(), ", ")); //ps.setString(4, movie.getType().get(0)); ps.addBatch(); } ps.executeBatch(); conn.commit(); } catch (SQLException e) { e.printStackTrace(); } finally { try { ps.close(); conn.close(); } catch (SQLException e) { e.printStackTrace(); } } } public static Movie getMovieById(int movieID){ Connection conn = DBUtil.getConnection(); PreparedStatement ps = null; ResultSet rs = null; Movie movie = null; String sql = "SELECT * FROM " + TABLE_NAME + " WHERE " + ID_COLUMN + " = "+movieID+" "; try { conn.setAutoCommit(false); ps = conn.prepareStatement(sql); rs = ps.executeQuery(); while(rs.next()){ movie = constructMovieFromResultSet(rs); } return movie; } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } public static Movie constructMovieFromResultSet(ResultSet rs){ try { Movie movie = new Movie(); movie.setId(rs.getInt(ID_COLUMN)); movie.setName(rs.getString(NAME_COLUMN)); String type = rs.getString(TYPE_COLUMN); if(type != null){ movie.setType(Arrays.asList(type.split(", "))); } return movie; } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return null; } public static List<Movie> getMovies(Collection<Integer> movieIDs){ List<Movie> movies = new ArrayList<Movie>(); String movieIDString = StringUtil.connectString(movieIDs); String sql = "SELECT * FROM " + TABLE_NAME + " WHERE " + ID_COLUMN + " IN ( " + movieIDString + " )"; Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; try { //conn = DBUtil.getConnectionFromDataSource(); conn = DBUtil.getConnection(); pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(); // conn = DBUtil.getConnection(); // pstmt = conn.prepareStatement(sql); // rs = pstmt.executeQuery(); while (rs.next()) { Movie movie = constructMovieFromResultSet(rs); if(movie != null){ movies.add(movie); } } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { try { rs.close(); pstmt.close(); conn.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } return movies; } public static Map<String, Movie> getMovieMap(Collection<String> movieIDs){ Map<String, Movie> movies = new HashMap<String, Movie>(); String movieIDString = StringUtil.connectString(movieIDs, ", "); String sql = "SELECT * FROM " + TABLE_NAME + " WHERE " + ID_COLUMN + " IN ( " + movieIDString + " )"; Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; try { conn = DBUtil.getConnectionFromDataSource(); pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(); // conn = DBUtil.getConnection(); // pstmt = conn.prepareStatement(sql); // rs = pstmt.executeQuery(); while (rs.next()) { Movie movie = constructMovieFromResultSet(rs); if(movie != null){ movies.put(String.valueOf(movie.getId()), movie); } } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { try { rs.close(); pstmt.close(); conn.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } return movies; } public static List<Integer> getAllMoviesId(){ List<Integer> ids=new ArrayList<Integer>(); String sql = "SELECT "+ ID_COLUMN +" FROM " + TABLE_NAME; Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; conn = DBUtil.getConnection(); try { pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(); while(rs.next()){ int aa=rs.getInt(ID_COLUMN); ids.add(aa); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return ids; } public static List<Movie> getAllMovies(){ List<Movie> movies = new ArrayList<Movie>(); String sql = "SELECT * FROM " + TABLE_NAME; Connection conn = null; PreparedStatement pstmt = null; ResultSet rs = null; try { // conn = DBUtil.getConnectionFromDataSource(); // pstmt = conn.prepareStatement(sql); // rs = pstmt.executeQuery(); conn = DBUtil.getConnection(); pstmt = conn.prepareStatement(sql); rs = pstmt.executeQuery(); while (rs.next()) { Movie movie = constructMovieFromResultSet(rs); if(movie != null){ movies.add(movie); } } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } finally { try { rs.close(); pstmt.close(); conn.close(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } return movies; } }