一个善良的码农

工具类——MyBatis 不需要log4j就可以打印出SQL语句

//工具类：


import java.lang.reflect.Field;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Collection;
import java.util.List;
import java.util.Map;
import java.util.Properties;
import org.apache.ibatis.executor.ErrorContext;
import org.apache.ibatis.executor.ExecutorException;
import org.apache.ibatis.executor.statement.BaseStatementHandler;
import org.apache.ibatis.executor.statement.RoutingStatementHandler;
import org.apache.ibatis.executor.statement.StatementHandler;
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.Interceptor;
import org.apache.ibatis.plugin.Intercepts;
import org.apache.ibatis.plugin.Invocation;
import org.apache.ibatis.plugin.Plugin;
import org.apache.ibatis.plugin.Signature;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.property.PropertyTokenizer;
import org.apache.ibatis.scripting.xmltags.ForEachSqlNode;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.defaults.DefaultSqlSession.StrictMap;
import org.apache.ibatis.type.TypeHandler;
import org.apache.ibatis.type.TypeHandlerRegistry;
/**
 * Sql执行时间记录拦截器
 */
@Intercepts({@Signature(type = StatementHandler.class, method = "query", args = {Statement.class, ResultHandler.class}),
@Signature(type = StatementHandler.class, method = "update", args = {Statement.class}),
@Signature(type = StatementHandler.class, method = "batch", args = {Statement.class })})
public class SqlCostInterceptor implements Interceptor {

    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        Object target = invocation.getTarget();

        long startTime = System.currentTimeMillis();
        StatementHandler statementHandler = (StatementHandler)target;
        try {
            return invocation.proceed();
        } finally {
            long endTime = System.currentTimeMillis();
            long sqlCost = endTime - startTime;

            BoundSql boundSql = statementHandler.getBoundSql();
            String sql = boundSql.getSql();
            Object parameterObject = boundSql.getParameterObject();
            List parameterMappingList = boundSql.getParameterMappings();

            // 格式化Sql语句，去除换行符，替换参数
            sql = formatSql(sql, parameterObject, parameterMappingList);

            System.out.println("SQL：[" + sql + "]执行耗时[" + sqlCost + "ms]");
        }
    }

    @Override
    public Object plugin(Object target) {
        return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {

    }

    @SuppressWarnings("unchecked")
    private String formatSql(String sql, Object parameterObject, List parameterMappingList) {
        // 输入sql字符串空判断
        if (sql == null || sql.length() == 0) {
            return "";
        }

        // 美化sql
        sql = beautifySql(sql);

        // 不传参数的场景，直接把Sql美化一下返回出去
        if (parameterObject == null || parameterMappingList == null || parameterMappingList.size() == 0) {
            return sql;
        }

        // 定义一个没有替换过占位符的sql，用于出异常时返回
        String sqlWithoutReplacePlaceholder = sql;

        try {
            if (parameterMappingList != null) {
                Class parameterObjectClass = parameterObject.getClass();

                // 如果参数是StrictMap且Value类型为Collection，获取key="list"的属性，这里主要是为了处理循环时传入List这种参数的占位符替换
                // 例如select * from xxx where id in ...
                if (isStrictMap(parameterObjectClass)) {
                    StrictMap> strictMap = (StrictMap>)parameterObject;

                    if (isList(strictMap.get("list").getClass())) {
                        sql = handleListParameter(sql, strictMap.get("list"));
                    }
                } else if (isMap(parameterObjectClass)) {
                    // 如果参数是Map则直接强转，通过map.get(key)方法获取真正的属性值
                    // 这里主要是为了处理、、、