java導出數據庫的結構 表結構 字段信息 主鍵

 工做之餘，用java寫了一個導出數據庫結構的小工具，附上核心代碼

Table.java

 

package org.dev.livvy.db;

import java.util.List;

/**
 * Created with IntelliJ IDEA.
 * User: GuoZheng
 * Date: 13-1-10
 * Time: 下午2:02
 * To change this template use File | Settings | File Templates.
 */
public class Table {
    /**
     * 表名稱
     */
    private String name;
    /**
     * 存儲空間(庫名)
     */
    private String space;
    /**
     * 表中的列
     */
    List<Column> columns;

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public String getSpace() {
        return space;
    }

    public void setSpace(String space) {
        this.space = space;
    }


    public List<Column> getColumns() {
        return columns;
    }

    public void setColumns(List<Column> columns) {
        this.columns = columns;
    }

    @Override
    public String toString() {
        return "Table{" +
                "name='" + name + '\'' +
                ", space='" + space + '\'' +
                ", columns=" + columns +
                '}';
    }
}

Column.java

 

package org.dev.livvy.db;

/**
 * Created with IntelliJ IDEA.
 * User: GuoZheng
 * Date: 13-1-10
 * Time: 下午2:09
 * To change this template use File | Settings | File Templates.
 */
public class Column {
    /**
     * 表名稱
     */
    private String tableName;
    /**
     * 列名稱(字段名稱)
     */
    private String name;
    /**
     * 是否主鍵
     */
    private  int isPk;
    /**
     * 默認值
     */
    private String value;
    /**
     * 是否爲空
     */
    private int isNotNull;
    /**
     * 數據類型
     */
    private String type;
    /**
     * 數據長度
     */
    private int length;
    /**
     * 代碼類型
     */
    private int codeType;

    public String getTableName() {
        return tableName;
    }

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

    public String getName() {
        return name;
    }

    public void setName(String name) {
        this.name = name;
    }

    public int getPk() {
        return isPk;
    }

    public void setPk(int pk) {
        isPk = pk;
    }

    public String getValue() {
        return value;
    }

    public void setValue(String value) {
        this.value = value;
    }

    public int getNotNull() {
        return isNotNull;
    }

    public void setNotNull(int notNull) {
        isNotNull = notNull;
    }

    public String getType() {
        return type;
    }

    public void setType(String type) {
        this.type = type;
    }

    public int getLength() {
        return length;
    }

    public void setLength(int length) {
        this.length = length;
    }

    public int getCodeType() {
        return codeType;
    }

    public void setCodeType(int codeType) {
        this.codeType = codeType;
    }

    @Override
    public String toString() {
        return "Column{" +
                "tableName='" + tableName + '\'' +
                ", name='" + name + '\'' +
                ", isPk=" + isPk +
                ", value='" + value + '\'' +
                ", isNotNull=" + isNotNull +
                ", type='" + type + '\'' +
                ", length=" + length +
                ", codeType=" + codeType +
                '}';
    }
}

DBAnalysis.java數據庫分析類

 

package org.dev.livvy.db;

import java.sql.*;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * Created with IntelliJ IDEA.
 * User: GuoZheng
 * Date: 13-1-10
 * Time: 上午11:18
 * To change this template use File | Settings | File Templates.
 */
public class DBAnalysis {

    private Connection connection;

    private DBAnalysis(String connStr, String db, String username, String password) throws ClassNotFoundException, SQLException {
        Class.forName("com.mysql.jdbc.Driver");
        connection = DriverManager.getConnection(connStr + db, username, password);
    }

    private static DBAnalysis instance = null;

    private static DBAnalysis getInstance(String connStr, String db, String username, String password) throws SQLException, ClassNotFoundException {
        if (instance == null) {
            instance = new DBAnalysis(connStr, db, username, password);
        }
        return instance;
    }

    private static Connection getConnection(String connStr, String db, String username, String password) throws SQLException, ClassNotFoundException {
        return getInstance(connStr, db, username, password).connection;
    }

    /**
     * 獲取表的主鍵
     * @param conn 數據庫鏈接
     * @param tableName  表名
     * @return 表中的主鍵
     * @throws SQLException
     */
    private static List getPks(Connection conn, String tableName) throws SQLException {
        List pks = new ArrayList();
        ResultSet rsPks = conn.getMetaData().getPrimaryKeys(null, null, tableName);

        while (rsPks.next()) {
            pks.add(rsPks.getString("COLUMN_NAME"));
        }
        rsPks.close(); //關閉
        return pks;
    }

    /**
     *  獲取全部的列信息
     * @param conn 數據庫鏈接
     * @param tableName 表名
     * @return 列的詳細信息
     * @throws SQLException
     */
    private static List<Column> getColumns(Connection conn,String tableName) throws SQLException {
        List<Column> cols = new ArrayList<Column>();
        //獲取這個表的主鍵 ，並存儲在list中
        List pks = getPks(conn,tableName);
        Statement stmt = conn.createStatement();
        ResultSet rs = stmt.executeQuery("select * from " + tableName);                                   //此處須要優化 limit 1 top 1 rownum <= 1  根據不一樣數據庫
        ResultSetMetaData rsCols = rs.getMetaData();
        int columnCount = rsCols.getColumnCount();
        for (int i = 1; i <= columnCount; i++) {
            Column col = new Column();
            col.setTableName(rsCols.getTableName(i));
            col.setName(rsCols.getColumnName(i));
            col.setType(rsCols.getColumnTypeName(i));
            col.setPk(pks.contains(rsCols.getColumnName(i)) ? 1 : 0);
            col.setLength(rsCols.getColumnDisplaySize(i));
            col.setNotNull(rsCols.isNullable(i) == 0 ? 1 : 0);
            cols.add(col);
        }
        rs.close();
        stmt.close();
        return cols;
    }

    /**
     * 獲取全部表信息
     * @param connStr  數據庫鏈接字符串
     * @param db 鏈接的庫
     * @param username  數據庫用戶名
     * @param password   數據庫密碼
     * @return  庫中表信息
     * @throws SQLException
     * @throws ClassNotFoundException
     */
    public static List<Table> collectAllTables(String connStr, String db, String username, String password) throws SQLException, ClassNotFoundException {
        Connection conn = getConnection(connStr, db, username, password);
        return collectAllTables(conn,db);
    }

    /**
     *  獲取全部表信息
     * @param conn 數據庫鏈接 s
     * @param db 數據庫
     * @return  庫中表信息
     * @throws SQLException
     */
    public static List<Table> collectAllTables(Connection conn,String db) throws SQLException {
        DatabaseMetaData dmd = conn.getMetaData();

        //獲取庫中的全部表
        ResultSet rsTables = dmd.getTables(null, null, null, new String[]{"TABLE"});
        List<Table> tables = new ArrayList<Table>();
        //將表存到list中
        while (rsTables.next()) {
            Table tb = new Table();
            tb.setSpace(db);
            //獲取表名稱
            String tbName = rsTables.getString("TABLE_NAME");
            tb.setName(tbName);

            //獲取表中的字段及其類型
            List<Column> cols = getColumns(conn,tbName);
            tb.setColumns(cols);
            tables.add(tb);
        }
        rsTables.close();

        return tables;           //connection未關閉
    }
}