plugins

package com.feixiang.plugin;

import org.apache.ibatis.executor.statement.StatementHandler;
import org.apache.ibatis.plugin.*;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.SystemMetaObject;

import java.sql.Connection;
import java.util.Properties;

@Intercepts({
    @Signature(
        type = StatementHandler.class,
        method = "prepare",
        args = {Connection.class, Integer.class}
    )
})
public class SqlExecutionTimePlugin implements Interceptor {

    private long slowThreshold = 1000; // 慢查询阈值，单位毫秒

    @Override
    public Object intercept(Invocation invocation) throws Throwable {
        // 获取目标 StatementHandler
        StatementHandler target = (StatementHandler) invocation.getTarget();
        MetaObject metaObject = SystemMetaObject.forObject(target);

        // 获取即将执行的 SQL（通过 BoundSql）
        String sql = (String) metaObject.getValue("delegate.boundSql.sql");
        sql = sql.replaceAll("[\s]+", " "); // 压缩多余空白

        long start = System.currentTimeMillis();
        try {
            // 执行目标方法
            return invocation.proceed();
        } finally {
            long cost = System.currentTimeMillis() - start;
            if (cost > slowThreshold) {
                System.out.println("【慢查询告警】SQL: " + sql + " | 耗时: " + cost + "ms");
            } else {
                System.out.println("【SQL监控】SQL: " + sql + " | 耗时: " + cost + "ms");
            }
        }
    }

    @Override
    public Object plugin(Object target) {
        // 使用 MyBatis 提供的 Plugin.wrap 创建代理
        return Plugin.wrap(target, this);
    }

    @Override
    public void setProperties(Properties properties) {
        String threshold = properties.getProperty("slowThreshold");
        if (threshold != null) {
            this.slowThreshold = Long.parseLong(threshold);
        }
        System.out.println("【SqlExecutionTimePlugin】初始化完成，慢查询阈值: " + slowThreshold + "ms");
    }
}

public class PluginDemo {
    public static void main(String[] args) throws Exception {
        InputStream is = Resources.getResourceAsStream("mybatis-config.xml");
        SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(is);

        try (SqlSession session = factory.openSession()) {
            EmployeeMapper mapper = session.getMapper(EmployeeMapper.class);
            
            // 执行查询
            Employee emp = mapper.selectById(1);
            System.out.println("查询结果: " + emp.getEmployeeName());
        }
    }
}