工具类自动生成数据库表结构数据库字典

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前言

项目开发完毕后，需要写文档，其中有一个就是整理数据库的表结构，一个一个手写太麻烦了，网上找了一个工具类自动生成excel文档

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代码如下（示例）：

 package com.guidao.pathwayManage.web.util;
import java.io.FileOutputStream;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.util.HashMap;
import java.util.Map;
import java.util.Set;

import org.apache.commons.collections4.MapUtils;
import org.apache.poi.hssf.usermodel.HSSFCell;
import org.apache.poi.hssf.usermodel.HSSFRow;
import org.apache.poi.hssf.usermodel.HSSFSheet;
import org.apache.poi.hssf.usermodel.HSSFWorkbook;
import org.apache.poi.ss.usermodel.CellStyle;
import org.apache.poi.ss.usermodel.FillPatternType;
import org.apache.poi.ss.usermodel.Font;
import org.apache.poi.ss.usermodel.HorizontalAlignment;
import org.apache.poi.ss.usermodel.IndexedColors;
import org.apache.poi.ss.usermodel.VerticalAlignment;
import org.apache.poi.ss.usermodel.Workbook;
import org.apache.poi.ss.util.CellRangeAddress;
import org.apache.poi.xssf.usermodel.XSSFCell;
import org.apache.poi.xssf.usermodel.XSSFRow;
import org.apache.poi.xssf.usermodel.XSSFSheet;
import org.apache.poi.xssf.usermodel.XSSFWorkbook;

/**
 * 生成数据库数据结构速查文件（数据库字典）
 * 

 */
public class ProduceGuideOfDatabase {

   
    public static void main(String[] args) {
        System.out.println("开始运行程序。。。");
        long preTime = System.currentTimeMillis();
        // 程序访问数据库拉取字典数据-程序整合成字典文件（配置数据库连接、要拉取得库名，一键运行代码即可）
        reArrangeFromSQL();
        System.out.println("运行完成，耗时：" + (System.currentTimeMillis() - preTime) + "ms");
    }

    /**
     * 直接从SQL中读取数据进行重整成excel
     */
    private static void reArrangeFromSQL() {
        String ip = "192.168.1.xxx", user = "数据库用户", password = "密码", database = "information_schema";
        Map<String, Map<String, TablePojo>> database_tables = new HashMap<>();
        try {
            String sqlStr = "SELECT pretab.TABLE_NAME AS 表名,pretab.TABLE_COMMENT AS 表释义,precol.COLUMN_NAME AS 字段名,precol.COLUMN_TYPE AS 字段类型, precol.COLUMN_DEFAULT AS 字段默认值,precol.COLUMN_COMMENT AS 表字段释义 FROM information_schema.`TABLES` AS pretab RIGHT JOIN information_schema.`COLUMNS` AS precol ON precol.TABLE_NAME=pretab.TABLE_NAME WHERE pretab.TABLE_SCHEMA =? GROUP BY precol.TABLE_NAME,precol.COLUMN_NAME ORDER BY precol.TABLE_NAME;";
            Connection connection = getConnection(ip, user, password, database);
            PreparedStatement pstmt = connection.prepareStatement(sqlStr);
            ResultSet rs = null;
            String[] databaseNames = "数据库名"
                    .split("-");
            for (String databaseName : databaseNames) {
                pstmt.setString(1, databaseName);
                rs = pstmt.executeQuery();// 获取数据
                String columnLines = "";
                int countAll = 0;// 表总数
                Map<String, TablePojo> tableNames = new HashMap<>();
                String preTableName = "";
                String preTableComment = "";
                while (rs.next()) {
                    String currentTableName = isBlank(rs.getString(1)) ? "" : rs.getString(1);
                    if (tableNames.containsKey(getRealTablename(currentTableName))) {
                        continue;
                    }
                    String currentTableComment = isBlank(rs.getString(2)) ? "" : rs.getString(2);
                    String currentColumnName = isBlank(rs.getString(3)) ? "" : rs.getString(3);
                    String currentColumnType = isBlank(rs.getString(4)) ? "" : rs.getString(4);
                    String currentColumnDefault = isBlank(rs.getString(5)) ? "" : rs.getString(5);
                    String currentColumnComment = isBlank(rs.getString(6)) ? "" : rs.getString(6);
                    if (currentTableName.equals(preTableName)) {
                        columnLines += currentColumnName + "#" + currentColumnType + "#" + currentColumnDefault + "#"
                                + currentColumnComment + "@";
                        continue;
                    }
                    if (countAll != 0 && !tableNames.containsKey(getRealTablename(preTableName))) {
                        TablePojo tablePojo = new TablePojo(preTableName, preTableComment, columnLines.substring(0,
                                columnLines.length() - 1));
                        tableNames.put(getRealTablename(preTableName), tablePojo);
                    }
                    countAll++;
                    columnLines = currentColumnName + "#" + currentColumnType + "#" + currentColumnDefault + "#"
                            + currentColumnComment + "@";
                    preTableName = currentTableName;
                    preTableComment = currentTableComment;
                }
                // 最后一组数据判断+保存
               /* if (!tableNames.containsKey(getRealTablename(preTableName))) {
                    TablePojo tablePojo = new TablePojo(preTableName, preTableComment, columnLines.substring(0,
                            columnLines.length() - 1));
                    tableNames.put(getRealTablename(preTableName), tablePojo);
                }*/
                database_tables.put(databaseName, tableNames);
            }
            rs.close();
            pstmt.close();
            connection.close();
        } catch (Exception e) {
            e.printStackTrace();
        }
        String url = "C:\\Users\\liuyifeng\\Desktop\\";
        String forFile = "22222.xlsx";
        if (MapUtils.isNotEmpty(database_tables)) {
            if (forFile.contains(".xlsx")) {
                arrangeToXLSX(database_tables, url, forFile);
            } else {
                arrangeToXLS(database_tables, url, forFile);
            }
        }
    }

    /**
     * 取数据整合到excel-xls
     * @param tableNamesMap
     * @param fos
     */
    private static void arrangeToXLS(Map<String, Map<String, TablePojo>> database_tables, String url, String forFile) {
        try (FileOutputStream fos = new FileOutputStream(url + forFile);) {
            if (MapUtils.isNotEmpty(database_tables)) {
                HSSFWorkbook currentWorkbook = new HSSFWorkbook();
                // 获取所有样式
                Map<String, CellStyle> cellStyles = getCellStyles(currentWorkbook);
                Set<String> databaseNames = database_tables.keySet();
                for (String databaseName : databaseNames) {
                    HSSFSheet currentSheet = currentWorkbook.createSheet(databaseName);
                    HSSFRow currentRow = null;
                    HSSFCell currentCell = null;
                    int rowIndex = -1;
                    Map<String, TablePojo> tableNames = database_tables.get(databaseName);
                    for (TablePojo tablePojo : tableNames.values()) {
                        // 空行
                        currentSheet.createRow(++rowIndex);
                        // 表头
                        currentRow = currentSheet.createRow(++rowIndex);
                        currentRow.setHeightInPoints(18);
                        currentCell = currentRow.createCell(0);
                        currentCell.setCellStyle(cellStyles.get("bluesStyle"));
                        currentCell.setCellValue(tablePojo.getTableName() + "(" + tablePojo.getTableComment() + ")");
                        CellRangeAddress region = new CellRangeAddress(rowIndex, rowIndex, 0, 3);
                        currentSheet.addMergedRegion(region);
                        // 表-标题栏
                        currentRow = currentSheet.createRow(++rowIndex);
                        currentRow.setHeightInPoints(18);
                        currentCell = currentRow.createCell(0);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("字段名");
                        currentCell = currentRow.createCell(1);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("类型");
                        currentCell = currentRow.createCell(2);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("默认值");
                        currentCell = currentRow.createCell(3);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("描述");
                        // 表字段
                        String tableColumnsStr = tablePojo.getTableColumns();
                        for (String tableColumns : tableColumnsStr.split("@")) {
                            currentRow = currentSheet.createRow(++rowIndex);
                            currentRow.setHeightInPoints(18);
                            String[] tableColumnArr = tableColumns.split("#");
                            for (int i = 0; i < tableColumnArr.length; i++) {
                                currentCell = currentRow.createCell(i);
                                currentCell.setCellStyle(cellStyles.get("baseStyle"));
                                currentCell.setCellValue(tableColumnArr[i]);
                            }
                        }
                    }
                }
                currentWorkbook.write(fos);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 取数据整合到excel-xlsx
     */
    private static void arrangeToXLSX(Map<String, Map<String, TablePojo>> database_tables, String url, String forFile) {
        try (FileOutputStream fos = new FileOutputStream(url + forFile);) {
            if (MapUtils.isNotEmpty(database_tables)) {
                XSSFWorkbook currentWorkbook = new XSSFWorkbook();
                // 获取所有样式
                Map<String, CellStyle> cellStyles = getCellStyles(currentWorkbook);
                Set<String> databaseNames = database_tables.keySet();
                for (String databaseName : databaseNames) {
                    XSSFSheet currentSheet = currentWorkbook.createSheet(databaseName);
                    XSSFRow currentRow = null;
                    XSSFCell currentCell = null;
                    int rowIndex = -1;
                    Map<String, TablePojo> tableNames = database_tables.get(databaseName);
                    for (TablePojo tablePojo : tableNames.values()) {
                        // 空行
                        currentSheet.createRow(++rowIndex);
                        // 表头
                        currentRow = currentSheet.createRow(++rowIndex);
                        currentRow.setHeightInPoints(18);
                        currentCell = currentRow.createCell(0);
                        currentCell.setCellStyle(cellStyles.get("bluesStyle"));
                        currentCell.setCellValue(tablePojo.getTableName() + "(" + tablePojo.getTableComment() + ")");
                        CellRangeAddress region = new CellRangeAddress(rowIndex, rowIndex, 0, 3);
                        currentSheet.addMergedRegion(region);
                        // 表-标题栏
                        currentRow = currentSheet.createRow(++rowIndex);
                        currentRow.setHeightInPoints(18);
                        currentCell = currentRow.createCell(0);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("字段名");
                        currentCell = currentRow.createCell(1);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("类型");
                        currentCell = currentRow.createCell(2);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("默认值");
                        currentCell = currentRow.createCell(3);
                        currentCell.setCellStyle(cellStyles.get("blueStyle"));
                        currentCell.setCellValue("描述");
                        // 表字段
                        String tableColumnsStr = tablePojo.getTableColumns();
                        for (String tableColumns : tableColumnsStr.split("@")) {
                            currentRow = currentSheet.createRow(++rowIndex);
                            currentRow.setHeightInPoints(18);
                            String[] tableColumnArr = tableColumns.split("#");
                            for (int i = 0; i < tableColumnArr.length; i++) {
                                currentCell = currentRow.createCell(i);
                                currentCell.setCellStyle(cellStyles.get("baseStyle"));
                                currentCell.setCellValue(tableColumnArr[i]);
                            }
                        }
                    }
                }
                currentWorkbook.write(fos);
            }
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * 样式集锦
     * 
     * @author ruran
     */
    private static Map<String, CellStyle> getCellStyles(Workbook workbook) {
        // 实线边框
        // style1.setBorderTop(BorderStyle.THIN);
        // style1.setBorderBottom(BorderStyle.THIN);
        // style1.setBorderLeft(BorderStyle.THIN);
        // style1.setBorderRight(BorderStyle.THIN);
        // 设置自动换行
        // baseStyle.setWrapText(true);

        Map<String, CellStyle> cellStylesMap = new HashMap<>();
        // baseStyle
        CellStyle baseStyle = workbook.createCellStyle();
        // 水平对齐方式
        baseStyle.setAlignment(HorizontalAlignment.LEFT);
        // 垂直对齐方式
        baseStyle.setVerticalAlignment(VerticalAlignment.CENTER);
        // 宋体设置
        Font baseFont = workbook.createFont();
        baseFont.setFontName("宋体");
        baseStyle.setFont(baseFont);
        cellStylesMap.put("baseStyle", baseStyle);// 存放样式-baseStyle

        // 深蓝色底部、白色字体、加粗
        CellStyle bluesStyle = workbook.createCellStyle();
        bluesStyle.cloneStyleFrom(cellStylesMap.get("baseStyle"));// 继承某样式
        // 背景色
        bluesStyle.setFillForegroundColor(IndexedColors.ROYAL_BLUE.getIndex());
        bluesStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);// 这一行是必须的，不然会得不到想要的结果
        // 白色加粗字体
        Font bluesFont = workbook.createFont();
        bluesFont.setColor(IndexedColors.WHITE.getIndex());
        bluesFont.setBold(true);
        bluesFont.setFontName("宋体");
        bluesStyle.setFont(bluesFont);
        cellStylesMap.put("bluesStyle", bluesStyle);// 存放样式-bluesStyle

        // 浅蓝色底部
        CellStyle blueStyle = workbook.createCellStyle();
        blueStyle.cloneStyleFrom(cellStylesMap.get("baseStyle"));// 继承某样式
        // 背景色
        blueStyle.setFillForegroundColor(IndexedColors.PALE_BLUE.getIndex());
        blueStyle.setFillPattern(FillPatternType.SOLID_FOREGROUND);// 这一行是必须的，不然会得不到想要的结果
        cellStylesMap.put("blueStyle", blueStyle);// 存放样式-blueStyle

        return cellStylesMap;
    }

    /**
     * 字符串判非空
     */
    private static boolean isNotBlank(String str) {
        if (null == str) {
            return false;
        }
        if (str.trim().length() == 0) {
            return false;
        }
        return true;
    }

    /**
     * 字符串判非空
     * 
     * @author ruran
     */
    private static boolean isBlank(String str) {
        if (null == str) {
            return true;
        }
        if (str.trim().length() == 0) {
            return true;
        }
        return false;
    }

    /**
     * 获取真实的表名 - 逻辑是去除末尾的数字
     * 
     * @author ruran
     * @param tableName
     * @return
     */
    private static String getRealTablename(String tableName) {
        if (isBlank(tableName)) {
            return null;
        }
        return tableName.replaceAll("\\d+$", ""); 
        }
    
    /**
     * 获取数据连接
     * 
     * @author ruran
     * @param database
     * @return
     */
    private static Connection getConnection(String ip, String user, String password, String database) {
        try {
            Class.forName("com.mysql.jdbc.Driver");
            System.out.println("成功加载MySQL驱动程序...");
            Connection connention = DriverManager.getConnection("jdbc:mysql://" + ip + ":3306/" + database, user,
                    password);
            System.out.println("成功建立MySQL连接...");
            return connention;
        } catch (Exception e) {
            e.printStackTrace();
        }
        return null;
    }

    /**
     * 表数据内部类
     * 
     * @author ruran
     */
    @SuppressWarnings("unused")
    private static class TablePojo {
        String tableName = "";
        String tableComment = "";
        String tableColumns = "";

        public TablePojo() {

        }

        public TablePojo(String tablename, String tablecomment, String tablecolumns) {
            tableName = tablename;
            tableComment = tablecomment;
            tableColumns = tablecolumns;
        }

        public String getTableName() {
            return tableName;
        }

        public void setTableName(String tableName) {
            this.tableName = tableName;
        }

        public String getTableComment() {
            return tableComment;
        }

        public void setTableComment(String tableComment) {
            this.tableComment = tableComment;
        }

        public String getTableColumns() {
            return tableColumns;
        }

       public void setTableColumns(String tableColumns) {
             this.tableColumns = tableColumns;
        }
       }
    }