mybatis JdbcTypeInterceptor - 运行时自动添加 jdbcType 属性
上代码:
package tk.mybatis.plugin; import org.apache.ibatis.executor.ErrorContext; import org.apache.ibatis.executor.parameter.ParameterHandler; import org.apache.ibatis.mapping.BoundSql; import org.apache.ibatis.mapping.MappedStatement; import org.apache.ibatis.mapping.ParameterMapping; import org.apache.ibatis.mapping.ParameterMode; import org.apache.ibatis.plugin.*; import org.apache.ibatis.reflection.MetaObject; import org.apache.ibatis.scripting.defaults.DefaultParameterHandler; import org.apache.ibatis.session.Configuration; import org.apache.ibatis.type.JdbcType; import org.apache.ibatis.type.TypeHandler; import org.apache.ibatis.type.TypeHandlerRegistry; import java.lang.reflect.Field; import java.lang.reflect.Method; import java.math.BigDecimal; import java.math.BigInteger; import java.sql.PreparedStatement; import java.util.*; /** * JdbcTypeInterceptor - 运行时自动添加 jdbcType 属性 */ @Intercepts({ @Signature(type = ParameterHandler.class, method = "setParameters", args = {PreparedStatement.class}) }) public class JdbcTypeInterceptor implements Interceptor { private static Set<String> methodSet = new HashSet<>(); private static Map<Class<?>, JdbcType> typeMap = new HashMap<>(); private static final Field mappedStatementField; private static final Field boundSqlField; static { try { mappedStatementField = DefaultParameterHandler.class.getDeclaredField("mappedStatement"); mappedStatementField.setAccessible(true); } catch (NoSuchFieldException e) { throw new RuntimeException("获取 DefaultParameterHandler 字段 mappedStatement 时出错", e); } try { boundSqlField = DefaultParameterHandler.class.getDeclaredField("boundSql"); boundSqlField.setAccessible(true); } catch (NoSuchFieldException e) { throw new RuntimeException("获取 DefaultParameterHandler 字段 boundSql 时出错", e); } //设置默认的方法，是用 Mapper 所有方法 Method[] methods = tk.mybatis.mapper.common.Mapper.class.getMethods(); for (Method method : methods) { methodSet.add(method.getName()); } //设置默认的类型转换，参考 TypeHandlerRegistry register(Boolean.class, JdbcType.BOOLEAN); register(boolean.class, JdbcType.BOOLEAN); register(Byte.class, JdbcType.TINYINT); register(byte.class, JdbcType.TINYINT); register(Short.class, JdbcType.SMALLINT); register(short.class, JdbcType.SMALLINT); register(Integer.class, JdbcType.INTEGER); register(int.class, JdbcType.INTEGER); register(Long.class, JdbcType.BIGINT); register(long.class, JdbcType.BIGINT); register(Float.class, JdbcType.FLOAT); register(float.class, JdbcType.FLOAT); register(Double.class, JdbcType.DOUBLE); register(double.class, JdbcType.DOUBLE); register(String.class, JdbcType.VARCHAR); register(BigDecimal.class, JdbcType.DECIMAL); register(BigInteger.class, JdbcType.DECIMAL); register(Byte[].class, JdbcType.BLOB); register(byte[].class, JdbcType.BLOB); register(Date.class, JdbcType.DATE); register(java.sql.Date.class, JdbcType.DATE); register(java.sql.Time.class, JdbcType.TIME); register(java.sql.Timestamp.class, JdbcType.TIMESTAMP); register(Character.class, JdbcType.CHAR); register(char.class, JdbcType.CHAR); } @Override public Object intercept(Invocation invocation) throws Throwable { //这里不考虑有多个基于该方法插件时的情况 Object handler = invocation.getTarget(); MappedStatement mappedStatement = (MappedStatement) mappedStatementField.get(handler); //一旦配置了 methods，就只对配置的方法进行处理 if (handler instanceof DefaultParameterHandler) { if (methodSet.size() > 0) { String msId = mappedStatement.getId(); String methodName = msId.substring(msId.lastIndexOf(".") + 1); if (!methodSet.contains(methodName)) { return invocation.proceed(); } } //获取基本变量信息 BoundSql boundSql = (BoundSql) boundSqlField.get(handler); Object parameterObject = ((DefaultParameterHandler) handler).getParameterObject(); Configuration configuration = mappedStatement.getConfiguration(); TypeHandlerRegistry typeHandlerRegistry = configuration.getTypeHandlerRegistry(); PreparedStatement ps = (PreparedStatement) invocation.getArgs()[0]; //原 DefaultParameterHandler 逻辑 ErrorContext.instance().activity("setting parameters").object(mappedStatement.getParameterMap().getId()); List<ParameterMapping> parameterMappings = boundSql.getParameterMappings(); if (parameterMappings != null) { for (int i = 0; i < parameterMappings.size(); i++) { ParameterMapping parameterMapping = parameterMappings.get(i); if (parameterMapping.getMode() != ParameterMode.OUT) { Object value; String propertyName = parameterMapping.getProperty(); if (boundSql.hasAdditionalParameter(propertyName)) { // issue #448 ask first for additional params value = boundSql.getAdditionalParameter(propertyName); } else if (parameterObject == null) { value = null; } else if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) { value = parameterObject; } else { MetaObject metaObject = configuration.newMetaObject(parameterObject); value = metaObject.getValue(propertyName); } TypeHandler typeHandler = parameterMapping.getTypeHandler(); JdbcType jdbcType = parameterMapping.getJdbcType(); if (value == null && jdbcType == null) { if (parameterMapping.getJavaType() != null && typeMap.containsKey(parameterMapping.getJavaType())) { jdbcType = typeMap.get(parameterMapping.getJavaType()); } else { jdbcType = configuration.getJdbcTypeForNull(); } } typeHandler.setParameter(ps, i + 1, value, jdbcType); } } } return null; } return invocation.proceed(); } @Override public Object plugin(Object target) { return Plugin.wrap(target, this); } private boolean isNotEmpty(String str) { return str != null && str.length() > 0; } @Override public void setProperties(Properties properties) { String methodStr = properties.getProperty("methods"); if (isNotEmpty(methodStr)) { //处理所有方法 if (methodStr.equalsIgnoreCase("ALL")) { methodSet.clear(); } else { String[] methods = methodStr.split(","); for (String method : methods) { methodSet.add(method); } } } //手动配置 String typeMapStr = properties.getProperty("typeMaps"); if (isNotEmpty(typeMapStr)) { String[] typeMaps = typeMapStr.split(","); for (String typeMap : typeMaps) { String[] kvs = typeMap.split(":"); if (kvs.length == 2) { register(kvs[0], kvs[1]); } } } } public static void register(String type, String jdbcType) { try { typeMap.put(Class.forName(type), JdbcType.valueOf(jdbcType)); } catch (ClassNotFoundException e) { throw new RuntimeException("配置 typeMaps 时出错！", e); } } public static void register(Class<?> type, JdbcType jdbcType) { typeMap.put(type, jdbcType); } }
在springboot中使用:
@Bean public Interceptor getInterceptor(){ return new JdbcTypeInterceptor(); }
它的好处,就是在运行mybatis动态sql的时候给属性添加jdbcType
mybatis jdbctype参考:https://www.cnblogs.com/pianai-shu/p/6349183.html
