Java正则表达式未正确替换

Question

下面是我想替换几个字符串的代码片段。我在代码中的两个地方使用了date_add模式，但它只被替换了一次。我正在使用字符串。但对我来说还是不行。请帮我查明原因

public class Implementation {

 public static void main(String[] args) {
   String ipquery = "select  to_date(id)  from location_dim location_dim where ( location_name  =  '123' ) limit 10 union all select  item_id  " +
        "item_id  from  (select item_dim.time_id from item_dim item_dim where item_dim.time_id in  (  select time_dim.id from time_dim " +
        "where (( time_dim . day ) = date_add( '1999-01-01' ,  2 )) ) ) item_dim inner join time_dim  time_dim  on (( item_dim . time_id ) " +
        "= ( time_dim . id )) where (( time_dim . day ) = date_add( '1999-01-01' ,  2 )) limit 20";
   System.out.println(replace(ipquery));

 }

public static String replace(String query) {
  Map<String, String> imputnmatch = new HashMap<String, String>();
  imputnmatch.put("to_date", "date");
  imputnmatch.put("format_number", "format");
  imputnmatch.put("date_sub\\((.*),\\s*([0-9]+\\s*)\\)",
      "date_sub($1, interval $2 day)");
  imputnmatch.put("date_add\\((.*),\\s*([0-9]+\\s*)\\)",
      "date_add($1, interval $2 day)");
  for (Map.Entry<String, String> entry : imputnmatch.entrySet()) {
    query = query.replaceAll(entry.getKey(), entry.getValue());
    System.out.println(entry.getKey() + "  " + entry.getValue() + "   " +query);
  }
  return query;
}

}

Answer 1

在"date_add\\((.*),\\s*([0-9]+\\s*)\\)"模式中.*将尝试找到最大的潜在匹配，因此它将尝试找到以date_add\\(开始并以,\\s*([0-9]+\\s*)\\)结束的部分，这意味着在数据中

select to_date(id) from location_dim location_dim where ( location_name = '123' ) limit 10 union all select item_id item_id from (select item_dim.time_id from item_dim item_dim where item_dim.time_id in ( select time_dim.id from time_dim where (( time_dim . day ) = date_add( '1999-01-01' , 2 )) ) ) item_dim inner join time_dim time_dim on (( item_dim . time_id ) = ( time_dim . id )) where (( time_dim . day ) = date_add( '1999-01-01' , 2 )) limit 20

它会匹配的

select to_date(id) from location_dim location_dim where ( location_name = '123' ) limit 10 union all select item_id item_id from (select item_dim.time_id from item_dim item_dim where item_dim.time_id in ( select time_dim.id from time_dim where (( time_dim . day ) = date_add( '1999-01-01' , 2 )) ) ) item_dim inner join time_dim time_dim on (( item_dim . time_id ) = ( time_dim . id )) where (( time_dim . day ) = date_add( '1999-01-01' , 2 )) limit 20

要使.*搜索最小匹配，需要在*量词后面添加?使*量词不情愿（lazy）。所以试试看

"date_add\\((.*?),\\s*([0-9]+\\s*)\\)"
//             ^-add this

同样的规则适用于date_sub\\((.*),\\s*([0-9]+\\s*)\\)模式，这意味着您需要将其更改为date_sub\\((.*?),\\s*([0-9]+\\s*)\\)

Answer 2

您正在使用。*这也包括“）”所以你的一个日期子是包含在日期子模式中的。所以，改变你的约会时间；日期添加模式It will help you