获取字段名，获取数据库表字段名，获取数据库字段名，获取字段类型，获取数据库字段类型

package com.yirui.supervisor.service.sys.impl;

import com.yirui.supervisor.common.Column;
import com.yirui.supervisor.common.Table;
import com.yirui.supervisor.service.sys.SysService;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.stereotype.Service;

import javax.servlet.http.HttpServletResponse;
import java.io.OutputStream;
import java.sql.Connection;
import java.sql.DatabaseMetaData;
import java.sql.ResultSet;
import java.util.ArrayList;
import java.util.HashMap;
import java.util.List;
import java.util.Map;

@Service
public class SysServiceImpl implements SysService {


    @Value("${spring.datasource.driver-class-name}")
    private  String driverName;

    @Value("${spring.datasource.username}")
    private  String userName;

    @Value("${spring.datasource.password}")
    private  String userPwd;

    @Value("${spring.datasource.url}")
    private  String dbURL;

    @Override
    public void createSqlFile(HttpServletResponse response, String tbName) throws Exception{
        response.setContentType("application/octet-stream");
        response.setHeader("Content-Disposition", "attachment;filename="+new String((System.currentTimeMillis()+".sql").getBytes("utf-8"),"ISO-8859-1"));
        OutputStream out = response.getOutputStream();

        Map<String, Object> map = parseTable(tbName);
        Table tb = (Table) map.get("tb");
        ResultSet re = (ResultSet) map.get("re");
        Connection co = (Connection) map.get("co");
        List<Column> columns = tb.getColumns();
        while (re.next()){
            //删除语句生成
            String delSql="DELETE FROM "+tbName+" where id= ";
            //新增语法生成
            String insetSql="insert into "+tbName+" (";
            for(Column col :columns){
                insetSql+="`"+col.getDbName()+"`,";
            }
            insetSql=insetSql.substring(0,insetSql.length()-1);
            insetSql+=" )values ( ";


            for(Column col :columns){
                //删除语句生成
                if(col.getDbName().equals("id")){
                    if(col.getDbType().equalsIgnoreCase("int")){
                        delSql+=re.getInt("id");
                    }else{
                        delSql+="'"+re.getString("id")+"'";
                    }
                }

                if(col.getDbType().equalsIgnoreCase("Integer")||col.getDbType().equalsIgnoreCase("int")){
                    insetSql+=re.getObject(col.getDbName())+",";
                }else{
                    if(re.getString(col.getDbName())==null){
                        insetSql+=""+re.getString(col.getDbName())+",";
                    }else{
                        insetSql+="'"+re.getString(col.getDbName())+"',";
                    }

                }
            }
            insetSql=insetSql.substring(0,insetSql.length()-1)+")";
            out.write((delSql+";"+System.getProperty("line.separator")).getBytes());
            out.write((insetSql+";"+System.getProperty("line.separator")).getBytes());
        }
        co.close();
        out.flush();
        out.close();
    }



    private Map<String ,Object> parseTable(String tableName) throws Exception {

        String column = "%";

        Class.forName(driverName);
        Connection conn = java.sql.DriverManager.getConnection(dbURL, userName, userPwd);
        DatabaseMetaData dmd = conn.getMetaData();
        ResultSet rs = dmd.getColumns("", "", tableName, column);
        List<Column> columns = new ArrayList<Column>();
        while (rs.next()) {
            Column c = new Column();
            c.setLabel(rs.getString("REMARKS"));
            String name = rs.getString("COLUMN_NAME");
            c.setDbName(name);
            String dbType = rs.getString("TYPE_NAME");
            int columnSize = rs.getInt("COLUMN_SIZE");
            c.setDbType(dbType);
            c.setLength(rs.getInt("COLUMN_SIZE"));
            c.setDecimalDigits(rs.getInt("DECIMAL_DIGITS"));
            c.setNullable(rs.getBoolean("NULLABLE"));
            columns.add(c);
        }

        List<Column> pkColumns = new ArrayList<Column>();
        ResultSet pkrs = dmd.getPrimaryKeys("", "", tableName);
        while (pkrs.next()) {
            Column c = new Column();
            String name = pkrs.getString("COLUMN_NAME");
            c.setDbName(name);
            pkColumns.add(c);
        }



        Table t = new Table();
        t.setDbName(tableName);
        t.setColumns(columns);
        t.setPkColumns(pkColumns);
        ResultSet resultSet = conn.createStatement().executeQuery("select * from " + tableName);
        System.out.println(resultSet);
        Map<String, Object> map = new HashMap<>();
        map.put("tb",t);
        map.put("re",resultSet);
        map.put("co",conn);
        return map;
    }
}

package com.yirui.supervisor.common;

public class Column {

    private String name;
    private String dbName;
    private String label;
    private String type;
    private String dbType;
    private Integer length;
    private Boolean nullable;
    private Integer decimalDigits;


    public String getName() {
        return name;
    }

    public String getNameUpper() {
        return name.replaceFirst(name.substring(0, 1), name.substring(0, 1).toUpperCase());
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getLabel() {
        return label;
    }
    public void setLabel(String label) {
        this.label = label;
    }
    public String getType() {
        return type;
    }
    public void setType(String type) {
        this.type = type;
    }
    public Integer getLength() {
        return length;
    }
    public void setLength(Integer length) {
        this.length = length;
    }
    public Boolean getNullable() {
        return nullable;
    }
    public void setNullable(Boolean nullable) {
        this.nullable = nullable;
    }
    public Integer getDecimalDigits() {
        return decimalDigits;
    }
    public void setDecimalDigits(Integer decimalDigits) {
        this.decimalDigits = decimalDigits;
    }
    public String getDbName() {
        return dbName;
    }
    public void setDbName(String dbName) {
        this.dbName = dbName;
    }
    public String getDbType() {
        return dbType;
    }
    public void setDbType(String dbType) {
        this.dbType = dbType;
    }
}

package com.yirui.supervisor.common;

import java.util.List;

public class Table {
    private String name;
    private String dbName;
    private String tableDesc;
    private List<Column> columns;
    private List<Column> pkColumns;

    public String getName() {
        return name;
    }
    public String getNameUpper() {
        return name.replaceFirst(name.substring(0, 1), name.substring(0, 1).toUpperCase());
    }
    public void setName(String name) {
        this.name = name;
    }
    public String getDbName() {
        return dbName;
    }
    public void setDbName(String dbName) {
        this.dbName = dbName;
    }
    public String getTableDesc() {
        return tableDesc;
    }
    public void setTableDesc(String tableDesc) {
        this.tableDesc = tableDesc;
    }
    public List<Column> getColumns() {
        return columns;
    }
    public void setColumns(List<Column> columns) {
        this.columns = columns;
    }
    public List<Column> getPkColumns() {
        return pkColumns;
    }
    public void setPkColumns(List<Column> pkColumns) {
        this.pkColumns = pkColumns;
    }

}