map 에서 특정 문자열 포함된 값 가져와서 비교하기:: entrySet

public void setInsertLog(Map<String, Object> paramMap) { 

    // 기존값과 변경된 것만 처리
    paramMap.put("chg_column","");
    paramMap.put("his_bf" ,"");
    paramMap.put("his_af" ,"");

    Iterator<Entry<String, Object>> it = paramMap.entrySet().iterator();  
    while (it.hasNext()) {
        Entry<String, Object> entry = it.next(); 
        if(entry.getKey().contains("log_")){
            String newKey = entry.getKey().replace("log_", "");
            String newVal = (String)paramMap.get(newKey);

            if( !newVal.equals( entry.getValue()) ){
                paramMap.put("chg_column" , newKey );
                paramMap.put("his_bf" , entry.getValue() );
                paramMap.put("his_af" , newVal );
                contractDAO.setInsertContractLog(paramMap);
            }
        } 
    }  
}