CustomKeyGenerator.groovy

package com.company.cache

import com.google.common.base.Charsets
import com.google.common.hash.HashFunction
import com.google.common.hash.Hasher
import com.google.common.hash.Hashing
import com.vendavo.security.pseudo.SecUser
import org.springframework.cache.interceptor.KeyGenerator
import org.springframework.security.core.Authentication
import org.springframework.security.core.context.SecurityContextHolder

import java.lang.reflect.Method

class CustomKeyGenerator implements KeyGenerator {

    @Override
    Object generate(Object target, Method method, Object... params) {

        HashFunction hf = Hashing.sha512()
        Hasher hasher = hf.newHasher().putInt(target.hashCode())
        hasher.putString(method.returnType.canonicalName, Charsets.UTF_8)
        hasher.putString(method.declaringClass.canonicalName, Charsets.UTF_8)
        hasher.putString(method.parameterTypes.collect { it.canonicalName }.join(','), Charsets.UTF_8)

        params.findAll { it }.each { hasher.putInt(it.hashCode()) }

        Authentication authentication = SecurityContextHolder.context?.authentication

        if (authentication && authentication.principal) {
          // or get whetever parameter from security context principal...   
          hasher.putInt(authentication.principal.hashCode())
        }

        return hasher.hash().asLong()

    }
}

ehcache-context.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:cache="http://www.springframework.org/schema/cache" xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
           http://www.springframework.org/schema/beans/spring-beans-3.1.xsd http://www.springframework.org/schema/cache http://www.springframework.org/schema/cache/spring-cache.xsd http://www.springframework.org/schema/aop http://www.springframework.org/schema/aop/spring-aop.xsd"
       profile="cache">

    <cache:annotation-driven key-generator="keyGenerator"/>

    <bean id="keyGenerator" class="com.company.cache.TenantKeyGenerator"/>

    <bean id="cacheManager" class="org.springframework.cache.support.SimpleCacheManager">
        <property name="caches">
            <set>
                <bean class="org.springframework.cache.concurrent.ConcurrentMapCacheFactoryBean">
                    <property name="name" value="default"/>
                </bean>
            </set>
        </property>
    </bean>

</beans>

More about configuration: http://docs.spring.io/spring/docs/current/javadoc-api/org/springframework/cache/annotation/EnableCaching.html