Java RegEx 未替换所有预期模式

Question

我想要实现的目标是将比较等于替换为 ILIKE，而不是赋值语句。

即

SELECT * FROM db WHERE SUBJECT_TYPE = 'Person';

应替换为

SELECT * FROM db WHERE SUBJECT_TYPE ILIKE 'Person';

但是

SET session ABC.VAR = 5;

应保持不变。

为此，我尝试使用前瞻，以便在 等于 (=) 之前没有 SET。

Java

String str = "SELECT * FROM db WHERE SUBJECT_TYPE = 'Person' AND PREDICATE = 'name' AND OBJECT_VALUE = 'John' AND VERSION = '0' "
final Pattern EQUALS_ILIKE_PATTERN = Pattern.compile("(?i)((^((?!SET)[^=])+?)\\s*)=");

final Matcher matcher = EQUALS_ILIKE_PATTERN .matcher(str);

while (matcher.find())
{
    final String fromString = matcher.group(0);

    str = matcher.replaceAll("$1 ILIKE");
}

System.out.println(str);

实际结果:

SELECT * FROM db WHERE SUBJECT_TYPE ILIKE 'Person' AND PREDICATE = 'name' AND OBJECT_VALUE = 'John' AND VERSION = '0'

预期结果:

SELECT * FROM db WHERE SUBJECT_TYPE ILIKE 'Person' AND PREDICATE ILIKE 'name' AND OBJECT_VALUE ILIKE 'John' AND VERSION ILIKE '0'

此处的实际结果不会取代所有必要的等号 (=)。

Answer 1

我们可以通过对 String#replaceAll 的一行调用来完成此操作:

 String str = "SELECT * FROM db WHERE SUBJECT_TYPE = 'Person' AND PREDICATE = 'name' AND OBJECT_VALUE = 'John' AND VERSION = '0' ";
str = str.replaceAll("(WHERE|AND)\\s+(\\S+)\\s+=(?=\\s*'[^'+]+')", "$1 $2 ILIKE");
System.out.println(str);

此输出(为了便于阅读而格式化):

SELECT *
FROM db
WHERE
    SUBJECT_TYPE ILIKE 'Person' AND
    PREDICATE ILIKE 'name' AND
    OBJECT_VALUE ILIKE 'John' AND
    VERSION ILIKE '0'