本博客介绍了BeetlSQL3提供的高级扩展功能,以下问题可以在BeetlSQL3中轻易扩展实现
- 定义一个注解@Jackson能把属性对象转化成json存入到数据库
- 定义@LoadOne, 当数据加载完毕后,可以加载更多数据
- 定义@Matcher注解,影响Mapper的执行
- 多租户问题,通过定义@Tenant解决
- BeetlSQL 不支持BigInteger,如何自己扩展一个
- BeetlSQL 不支持Jackson的JsonNode,如何自己扩展
- 不喜欢BeetlSQL提供的json配置映射,自己想搞一个XML的
- BeetlSQL的默认映射方式足够好,但我想扩展自己的
- 给每个发送的DB的SQL的语句自动增加有个sqlId标记的注释,以方便DBA和程序员沟通,或者历史代码方便维护
- BeetlSQL的想把执行的SQL和参数输出到日志框架里。或者记录每次执行参数和结果
- 当底层执行JDBC的时候,我想为一些特殊的SQL增加特殊的JDBC设置
以上代码可以在 BeetlSQL Samples 找到
PluginAnnotationSample
/**
* 自定义注解演示
* @author xiandafu
* @see Jackson , json注解
* @see LoadOne, 加载更多数据
* @see Matcher, mapper扩展新注解
* @see Tenant,多租户注解
*
*/
public class PluginAnnotationSample {
SQLManager sqlManager;
public PluginAnnotationSample(SQLManager sqlManager) {
this.sqlManager = sqlManager;
}
public static void main(String[] args) throws Exception {
SQLManager sqlManager = SampleHelper.getSqlManager();
PluginAnnotationSample plugin = new PluginAnnotationSample(sqlManager);
plugin.testJacksonAnnotation();
plugin.testMatcherAnnotation();
plugin.loadMore();
plugin.tenant();
}
/**
* 自定义个Json注解 @Jackson,用于序列化到数据库,或者反序列化
*/
public void testJacksonAnnotation(){
UserInfo userInfo = new UserInfo();
Name name = new Name();
name.setFirstName("joel");
name.setLastName("li");
userInfo.setName(name);
sqlManager.insert(userInfo);
Integer id = userInfo.getId();
userInfo = sqlManager.unique(UserInfo.class,id);
System.out.println(userInfo.getName());
}
/**
* 自定义一个mapper的扩展注解@Matcher,使得mapper参数中有一个Condition类,能构造查询条件。
* 也演示了如何自定义BaseMapper和重新实现内置方法
*/
public void testMatcherAnnotation(){
MyMapper mapper = sqlManager.getMapper(MyMapper.class);
{
//@matcher注解
List<UserInfo> list = mapper.query(new Condition().append("name", Condition.Opt.equals)
,"lijz");
System.out.println(list.size());
}
{
// 重新实现的deleteById方法
try{
mapper.deleteById(1);
}catch(Exception ex){
System.out.println(ex.getMessage());
}
}
}
/**
* 查询数据后,在根据注解 @LoadOne定义加载更多数据
*/
public void loadMore(){
UserDetail userInfo = sqlManager.unique(UserDetail.class,1);
System.out.println(userInfo.getDepartmentId());
System.out.println(userInfo.getDept().getName());
}
/**
* 查询前根据注解 @Tenant,提供一些必要的上下文参数
*/
public void tenant(){
//设置当前操作的租户
TenantContext.tenantLocals.set(1);
String sql = "select * from user where department_id=#{tenantId}";
List<TenantUser> list = sqlManager.execute(sql,TenantUser.class,new HashMap());
System.out.println(list.get(0));
}
@Table(name="user")
@Data
public static class UserInfo{
@Column("id")
@AutoID
Integer id;
@Column("name")
@Jackson
Name name ;
}
@Data
public static class Name{
String firstName;
String lastName;
}
@Table(name="user")
@Data
@LoadOne(name="foo")
public static class UserDetail{
@Column("id")
@AutoID
Integer id;
String name;
Integer departmentId;
DepartmentInfo dept;
}
@Data
@Table(name="department")
public static class DepartmentInfo{
@Column("id")
@AutoID
Integer id;
String name;
}
@Data
@Table(name="user")
@Tenant
public static class TenantUser{
@Auto
private Integer id;
@Column("name")
private String name;
}
public interface MyMapper extends MyBaseMapper<UserInfo>{
/**
* Matcher是扩展注解,表示执行的sql,需要考虑Condition和后面的参数
* @param condition
* @param name
* @return
*/
@Matcher
List<UserInfo> query(Condition condition,String name);
}
/**
* 构造一个自定的Mapper方法,继承所有BaseMapper,但deleteById会做一些特殊逻辑
* @param <T>
*/
public static interface MyBaseMapper<T> extends BaseMapper{
@AutoMapper(DeleteCheckByIdAMI.class)
int deleteById(Object key);
}
public static class DeleteCheckByIdAMI extends MapperInvoke {
@Override
public Object call(SQLManager sm, Class entityClass, Method m, Object[] args) {
if(entityClass==UserInfo.class){
throw new IllegalArgumentException("不允许调用 "+entityClass);
}
return sm.deleteById(entityClass, args[0]);
}
}
}
MappingSample
演示如实如何实现TypeHandler转化BigInteger,和JsonNode,以及RowMapper,xml定义的ResultSetMapper,这些提供了灵活的映射
public class MappingSample {
SQLManager sqlManager;
public MappingSample(SQLManager sqlManager) {
this.sqlManager = sqlManager;
}
public static void main(String[] args) throws Exception {
SQLManager sqlManager = SampleHelper.getSqlManager();
MappingSample mappingSample = new MappingSample(sqlManager);
mappingSample.rowMapper();
mappingSample.typeHandler4BigInt();
mappingSample.typeHandler4JacksonNode();
mappingSample.xmlMapping();
}
/**
* 把查询结果集额外的列映射到属性上
*/
public void rowMapper(){
String sql = "select u.*,'[1,2]' col from user u where id=1 ";
UserVo info = sqlManager.execute(new SQLReady(sql), UserVo.class).get(0);
System.out.println(info.getExtraAttribute());
info = sqlManager.rowMapper(MyRowMapper.class).execute(new SQLReady(sql), UserVo.class).get(0);
System.out.println(info.getExtraAttribute());
//更常见的方式是通过注解RowProvider完成
info = sqlManager.execute(new SQLReady(sql), UserVo2.class).get(0);
System.out.println(info.getExtraAttribute());
}
/**
* 实现BigInteger转化
*/
public void typeHandler4BigInt(){
BigIntTypeHandler bigIntTypeHandler = new BigIntTypeHandler();
sqlManager.getDefaultBeanProcessors().addHandler(BigInteger.class,bigIntTypeHandler);
User2 user = new User2();
user.setName("lll");
user.setDepartmentId(new BigInteger("1"));
sqlManager.insert(user);
Integer id = user.getId();
User2 dbUser = sqlManager.unique(User2.class,1);
System.out.println(id+":"+dbUser.getDepartmentId());
}
/**
* 实现jackson node 转化
*/
public void typeHandler4JacksonNode(){
JsonNodeTypeHandler typeHandler = new JsonNodeTypeHandler();
/*注册需要处理的所有JsonNode子类*/
sqlManager.getDefaultBeanProcessors().addAcceptType(
new BeanProcessor.InheritedAcceptType(
JsonNode.class,typeHandler));
UserNode user = new UserNode();
JsonNode node = JsonNodeTypeHandler.objectMapper.createObjectNode().textNode("abcefg");
user.setName(node);
sqlManager.insert(user);
Integer id = user.getId();
UserNode dbUser = sqlManager.unique(UserNode.class,1);
System.out.println(id+":"+dbUser.getName());
}
/**
* 按照xml定义映射,SimpleXMLMapping实现了ResultSetMapper接口
*/
public void xmlMapping(){
User3 user = sqlManager.unique(User3.class,1);
System.out.println(user.getUserName());
}
@Data
public static class UserVo {
Integer id;
String name;
String extraAttribute;
}
@Data
@EqualsAndHashCode(callSuper = false)
@RowProvider(MyRowMapper.class)
public static class UserVo2 extends UserVo{
}
/**
* 把jsonNode存放到数据库,或者读取出来,在PluginAnnotation演示了通过自定义注解Jackson实现
* 这次我们可以换一个更底层的,实现一个类型处理器
*/
@Table(name="user")
@Data
public static class UserNode{
@Auto
Integer id;
JsonNode name;
}
@Table(name="user")
@Data
public static class User2{
@Auto
Integer id;
String name;
BigInteger departmentId;
}
/**
* 使用xml配置映射规则,参考user.xml,ResultProvider表示如何映射,XmlMapping是映射配置
*/
@Table(name="user")
@Data
@ResultProvider(SimpleXMLMapping.class)
@XmlMapping(path="user.xml")
public static class User3{
Integer id;
String userName;
Integer deptId;
}
/**
* Jackson的JsonNode类型处理类,使得java属性可以是JsonNode。
* 另外一种更通用的是PluginAnnotation例子中的@Jackson注解
*/
public static class JsonNodeTypeHandler extends JavaSqlTypeHandler{
static ObjectMapper objectMapper = new ObjectMapper();
@Override
public Object getValue(ReadTypeParameter typePara) throws SQLException {
String str = typePara.getRs().getString(typePara.getIndex());
JsonNode node = objectMapper.valueToTree(str);
return node;
}
@Override
public void setParameter(WriteTypeParameter writeTypeParameter, Object obj)throws SQLException {
JsonNode node = (JsonNode)obj;
try {
String text = objectMapper.writeValueAsString(node);
writeTypeParameter.getPs().setString(writeTypeParameter.getIndex(),text);
} catch (JsonProcessingException e) {
throw new IllegalArgumentException("不是json格式");
}
}
}
/**
* Beetlsql 并没有内置对BigInteger支持,这里可以扩展
*/
public static class BigIntTypeHandler extends JavaSqlTypeHandler{
static ObjectMapper objectMapper = new ObjectMapper();
@Override
public Object getValue(ReadTypeParameter typePara) throws SQLException {
BigDecimal decimal = typePara.getRs().getBigDecimal(typePara.getIndex());
return decimal.toBigInteger();
}
@Override
public void setParameter(WriteTypeParameter writeTypeParameter, Object obj)throws SQLException {
BigInteger bigInteger = (BigInteger)obj;
BigDecimal bigDecimal = new BigDecimal(bigInteger);
writeTypeParameter.getPs().setBigDecimal(writeTypeParameter.getIndex(),bigDecimal);
}
}
/**
* 自定义一个行映射
*/
public static class MyRowMapper implements RowMapper{
@Override
public Object mapRow(ExecuteContext ctx, Object obj, ResultSet rs, int rowNum, Annotation config) throws SQLException {
//内置的映射已经完成
UserVo vo = (UserVo)obj;
//额外取得结果集
String col = rs.getString("col");
vo.setExtraAttribute(col);
return vo;
}
}
}
InterceptSample
如何自定义Interceptor,定义了一个SqlIdAppendInterceptor,总是在sql语句最前面增加一个注释,注释内容为sqlId标识符,方便数据库dba与程序员沟通
public class InterceptSample {
public InterceptSample() {
}
public static void main(String[] args) throws Exception {
InterceptSample interceptSample = new InterceptSample();
interceptSample.appendSqlId();
interceptSample.debug();
}
/**
*在给执行的jdbc sql 增加一个注释
*/
public void appendSqlId(){
SQLManager sqlManager = SampleHelper.init();
//新增加一个Interceptor
List< Interceptor> interceptors = new ArrayList(Arrays.asList(sqlManager.getInters()));
SqlIdAppendInterceptor sqlIdAppendInterceptor = new SqlIdAppendInterceptor();
//放到第一个,这样后面的DebugInteceptor能打印出sql,实际项目应该放到最后
interceptors.add(0,sqlIdAppendInterceptor);
sqlManager.setInters(interceptors.toArray(new Interceptor[0]));
sqlManager.unique(UserEntity.class,1);
sqlManager.execute(new SQLReady("select * from user"), UserEntity.class);
}
/**
* 自带的DebugInterceptor输出详细信息到控制台,这里切换到用日志框架
*/
public void debug(){
SQLManager sqlManager = SampleHelper.init();
LogDebugInterceptor logDebugInterceptor = new LogDebugInterceptor();
sqlManager.setInters(new Interceptor[]{logDebugInterceptor});
sqlManager.unique(UserEntity.class,1);
}
public static class SqlIdAppendInterceptor implements Interceptor{
@Override
public void before(InterceptorContext ctx) {
ExecuteContext context = ctx.getExecuteContext();
String jdbcSql = context.sqlResult.jdbcSql;
String info = context.sqlId.toString();
//为发送到数据库的sql增加一个注释说明,方便数据库dba能与开发人员沟通
jdbcSql = "/*"+info+"*/\n"+jdbcSql;
context.sqlResult.jdbcSql = jdbcSql;
}
@Override
public void after(InterceptorContext ctx) {
//dothing
}
@Override
public void exception(InterceptorContext ctx, Exception ex) {
//do nothing
}
}
public static class LogDebugInterceptor extends DebugInterceptor {
Logger logger = Logger.getLogger("simple");
@Override
protected void println(String str) {
logger.log(Level.INFO,str);
}
@Override
protected void error(String str) {
logger.log(Level.SEVERE,str);
}
}
}
DbStyleSample
DbStyle 是Beetlsql的核心之一,这里演示如何扩展
public class DbStyleSample {
public DbStyleSample() {
}
public static void main(String[] args) throws Exception {
DbStyleSample dbStyleSample = new DbStyleSample();
dbStyleSample.preparedStatement();
}
public void preparedStatement(){
DataSource dataSource = SampleHelper.mysqlDatasource();
ConnectionSource source = ConnectionSourceHelper.getSingle(dataSource);
SQLManagerBuilder builder = new SQLManagerBuilder(source);
builder.setNc(new UnderlinedNameConversion());
builder.setInters(new Interceptor[]{new DebugInterceptor()});
//实现某些特殊功能
builder.setDbStyle(new MySqlDbStyle2());
SQLManager sqlManager = builder.build();
sqlManager.all(UserEntity.class);
}
public static class MySqlDbStyle2 extends MySqlStyle {
@Override
public SQLExecutor buildExecutor(ExecuteContext executeContext){
return new MyExecutor(executeContext);
}
/**
* 考虑jdbc fetch size
*/
public static class MyExecutor extends BaseSQLExecutor{
public MyExecutor(ExecuteContext executeContext) {
super(executeContext);
}
@Override
protected ResultSetHolder dbQuery(Connection conn, String sql, List<SQLParameter> jdbcPara) throws SQLException {
if(this.getExecuteContext().target!= UserEntity.class){
return super.dbQuery(conn,sql,jdbcPara);
}
//对于UserEntity对象查询,考虑使用特殊设置
PreparedStatement ps = conn.prepareStatement(sql,ResultSet.TYPE_FORWARD_ONLY, ResultSet.CONCUR_READ_ONLY);
ps.setFetchSize(100000);
this.setPreparedStatementPara(ps, jdbcPara);
ResultSet rs = ps.executeQuery();
return new ResultSetHolder(ps, rs);
}
}
}
}
来源:oschina
链接:https://my.oschina.net/xiandafu/blog/4462888