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操作步骤如下：
1. k8s环境下，consumer端开启mesh模式
2. consumer端需要调用多个provider
3. provider有应用级注册和接口级注册，并且需要的provider不再同一个namespace下
4. 原有项目存在dubbo2.6与3.1多版本间的相互调用，在开启消费端mesh（dubbo3.1）后，无法调用到2.6的服务提供者

**问题：**

1. 如何实现在一个consumer下，调用多个namespace下的provider，并且provider有应用级注册和接口级注册
2. dubbo3.1消费端在开启mesh后，如何调用版本是2.6的服务提供者
public void setGeneric(String generic) {
        if (StringUtils.isEmpty(generic)) {
            return;
        }
        if (ProtocolUtils.isValidGenericValue(generic)) {
            this.generic = generic;
        } else {
            throw new IllegalArgumentException("Unsupported generic type " + generic);
        }
    }
    /**
     * @return
     * @deprecated instead, use the parameter <b>scope</> to judge if it's in jvm, scope=local
     */
    @Deprecated
    public Boolean isInjvm() {
        return injvm;
    }
    /**
     * @param injvm
     * @deprecated instead, use the parameter <b>scope</b> to judge if it's in jvm, scope=local
     */
    @Deprecated
    public void setInjvm(Boolean injvm) {
        this.injvm = injvm;
    }
    @Override
    @Parameter(key = REFERENCE_FILTER_KEY, append = true)
    public String getFilter() {
        return super.getFilter();