springboot mybatis（不是mybatis-plus）多租户
public class TenantContext {
private static final ThreadLocal CURRENT_TENANT = new ThreadLocal<>();
public static void setTenantId(String tenantId) {
CURRENT_TENANT.set(tenantId);
}
public static String getTenantId() {
return CURRENT_TENANT.get();
}
public static void clear() {
CURRENT_TENANT.remove();
}
}
import net.sf.jsqlparser.JSQLParserException;
import net.sf.jsqlparser.expression.Expression;
import net.sf.jsqlparser.expression.StringValue;
import net.sf.jsqlparser.expression.operators.conditional.AndExpression;
import net.sf.jsqlparser.expression.operators.relational.EqualsTo;
import net.sf.jsqlparser.parser.CCJSqlParserUtil;
import net.sf.jsqlparser.schema.Column;
import net.sf.jsqlparser.statement.Statement;
import net.sf.jsqlparser.statement.delete.Delete;
import net.sf.jsqlparser.statement.select.PlainSelect;
import net.sf.jsqlparser.statement.select.Select;
import net.sf.jsqlparser.statement.update.Update;
import org.apache.ibatis.cache.CacheKey;
import org.apache.ibatis.executor.Executor;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.mapping.SqlSource;
import org.apache.ibatis.plugin.*;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.reflection.SystemMetaObject;
import org.apache.ibatis.session.ResultHandler;
import org.apache.ibatis.session.RowBounds;
import java.lang.reflect.Field;
import java.util.Map;
import java.util.Properties;
@Intercepts({
@Signature(type = Executor.class, method = "update", args = {MappedStatement.class, Object.class}),
@Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class}),
@Signature(type = Executor.class, method = "query", args = {MappedStatement.class, Object.class, RowBounds.class, ResultHandler.class, CacheKey.class, BoundSql.class}),
})
public class TenantInterceptor implements Interceptor {
private static final String TENANT_ID_COLUMN = "tenant_id"; // 租户字段名
@Override
public Object intercept(Invocation invocation) throws Throwable {
// 获取当前租户 ID
String tenantId = TenantContext.getTenantId();
if (tenantId == null) {
return invocation.proceed(); // 未设置租户，直接放行
}
// 获取 SQL 执行参数
Object[] args = invocation.getArgs();
MappedStatement mappedStatement = (MappedStatement) args[0];
Object parameter = args;
// 解析原始 SQL
BoundSql boundSql = mappedStatement.getBoundSql(parameter);
String originalSql = boundSql.getSql();
// 解析 SQL 并动态添加租户条件
String modifiedSql = modifySql(originalSql, tenantId);
BoundSql newBoundSql = new BoundSql(
mappedStatement.getConfiguration(),
modifiedSql,
boundSql.getParameterMappings(),
boundSql.getParameterObject());
MappedStatement newMs = buildMappedStatement(mappedStatement, new BoundSqlSqlSource(newBoundSql));
for (ParameterMapping mapping : boundSql.getParameterMappings()) {
String prop = mapping.getProperty();
if (boundSql.hasAdditionalParameter(prop)) {
newBoundSql.setAdditionalParameter(prop, boundSql.getAdditionalParameter(prop));
}
}
// 替换 MappedStatement
invocation.getArgs()[0] = newMs;
/* // 反射修改 SQL 内容
Field sqlField = boundSql.getClass().getDeclaredField("sql");
sqlField.setAccessible(true);
sqlField.set(boundSql, modifiedSql);*/
/*
// 注入 tenantId 到参数对象（用于 PreparedStatement 参数替换）
if (parameter != null) {
MetaObject metaObject = SystemMetaObject.forObject(parameter);
metaObject.setValue(TENANT_ID_COLUMN, tenantId);
}*/
return invocation.proceed();
}
// 修改 SQL 的核心逻辑（使用 JSqlParser 解析 SQL 语法树）
private String modifySql(String originalSql, String tenantId) {
try {
Statement statement = CCJSqlParserUtil.parse(originalSql);
if (statement instanceof Select) {
Select select = (Select) statement;
PlainSelect plainSelect = (PlainSelect) select.getSelectBody();
addTenantCondition(plainSelect.getWhere(), tenantId, select);
} else if (statement instanceof Update) {
Update update = (Update) statement;
addTenantCondition(update.getWhere(), tenantId, update);
} else if (statement instanceof Delete) {
Delete delete = (Delete) statement;
addTenantCondition(delete.getWhere(), tenantId, delete);
}
return statement.toString();
} catch (JSQLParserException e) {
throw new RuntimeException("SQL 解析失败", e);
}
}
// 向 WHERE 条件中添加租户过滤
private void addTenantCondition(Expression where, String tenantId, Statement statement) {
EqualsTo tenantCondition = new EqualsTo();
tenantCondition.setLeftExpression(new Column(TENANT_ID_COLUMN));
tenantCondition.setRightExpression(new StringValue(tenantId));
if (where == null) {
if (statement instanceof Update) {
((Update) statement).setWhere(tenantCondition);
} else if (statement instanceof Delete) {
((Delete) statement).setWhere(tenantCondition);
} else if (statement instanceof Select) {
((PlainSelect) ((Select) statement).getSelectBody()).setWhere(tenantCondition);
}
} else {
AndExpression and = new AndExpression(where, tenantCondition);
if (statement instanceof Update) {
((Update) statement).setWhere(and);
} else if (statement instanceof Delete) {
((Delete) statement).setWhere(and);
} else if (statement instanceof Select) {
((PlainSelect) ((Select) statement).getSelectBody()).setWhere(and);
}
}
}
@Override
public Object plugin(Object target) {
return Plugin.wrap(target, this);
}
@Override
public void setProperties(Properties properties) {}
/**
* 根据已有MappedStatement构造新的MappedStatement
*/
private MappedStatement buildMappedStatement(MappedStatement ms, SqlSource sqlSource) {
MappedStatement.Builder builder = new MappedStatement.Builder(ms.getConfiguration(), ms.getId(), sqlSource, ms.getSqlCommandType());
builder.resource(ms.getResource());
builder.fetchSize(ms.getFetchSize());
builder.statementType(ms.getStatementType());
builder.keyGenerator(ms.getKeyGenerator());
if (ms.getKeyProperties() != null && ms.getKeyProperties().length != 0) {
StringBuilder keyProperties = new StringBuilder();
for (String keyProperty : ms.getKeyProperties()) {
keyProperties.append(keyProperty).append(",");
}
keyProperties.delete(keyProperties.length() - 1, keyProperties.length());
builder.keyProperty(keyProperties.toString());
}
builder.timeout(ms.getTimeout());
builder.parameterMap(ms.getParameterMap());
builder.resultMaps(ms.getResultMaps());
builder.resultSetType(ms.getResultSetType());
builder.cache(ms.getCache());
builder.flushCacheRequired(ms.isFlushCacheRequired());
builder.useCache(ms.isUseCache());
return builder.build();
}
/**
* 用于构造新MappedStatement
*/
public static class BoundSqlSqlSource implements SqlSource {
BoundSql boundSql;
public BoundSqlSqlSource(BoundSql boundSql) {
this.boundSql = boundSql;
}
@Override
public BoundSql getBoundSql(Object parameterObject) {
return boundSql;
}
}
}由于原系统中引用了pagehelper-spring-boot-starter，并且PageInterceptor初始化比较晚，影响自定义多租户拦截器。需要把自定义拦截器的初始化放到最后，spring容器就绪后，初始化自定义mybatis拦截器
import org.apache.ibatis.session.SqlSessionFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.context.event.ApplicationReadyEvent;
import org.springframework.context.annotation.Configuration;
import org.springframework.context.event.EventListener;
@Configuration
public class TenantInterceptorConfig {
@Autowired
private SqlSessionFactory sqlSessionFactory;
@EventListener(ApplicationReadyEvent.class) // 应用启动完成后执行
public void addInterceptorAfterPageHelper() {
TenantInterceptor tenantInterceptor = new TenantInterceptor();
sqlSessionFactory.getConfiguration().addInterceptor(tenantInterceptor);
}
}