在java中转义点。 （StringEscapeUtil）

Question

这可能是一个超级愚蠢的问题，但我无法弄清楚为什么StringEscapeUtils以这种方式行事。

这是一个的失败，并出现以下错误第二断言：

org.junit.ComparisonFailure: Did not escape correctly Expected : t\.ext Actual : t.ext

测试

public class ServerDataTest { 
    @Test 
    public void escape() throws Exception { 
     assertEquals("Did not escape correctly", "text", ServerData.escape("text")); 
     assertEquals("Did not escape correctly", "t\\.ext", ServerData.escape("t.ext")); 
     assertEquals("Did not escape correctly", "te\\\\xt", ServerData.escape("te\\xt")); 
     assertEquals("Did not escape correctly", "te\\\\\\.xt", ServerData.escape("te\\.xt")); 
    } 
} 

逃避者实用

private final static Map<CharSequence, CharSequence> ESCAPE_MAP = new HashMap<>();{ 
     ESCAPE_MAP.put("\\", "\\\\"); 
     ESCAPE_MAP.put(".", "\\."); 
    } 

    private static LookupTranslator ESCAPE = new LookupTranslator(ESCAPE_MAP); 

    private final static Map<CharSequence, CharSequence> UNESCAPE_MAP = new HashMap<>();{ 
     UNESCAPE_MAP.put("\\\\", "\\"); 
     UNESCAPE_MAP.put("\\.", "."); 
    } 

    private static LookupTranslator UNESCAPE = new LookupTranslator(UNESCAPE_MAP); 

    static String escape(String text){ 
     return StringEscapeUtils.builder(ESCAPE).escape(text).toString(); 
    } 

    static String unescape(String text){ 
     return StringEscapeUtils.builder(UNESCAPE).escape(text).toString(); 
    } 

Answer 1

你永远都填静态地图ESCAPE_MAP和UNESCAPE_MAP，因为你忘记了关键字static。

下面是正确的代码

private final static Map<CharSequence, CharSequence> ESCAPE_MAP = new HashMap<>(); 
static { 
    ESCAPE_MAP.put("\\", "\\\\"); 
    ESCAPE_MAP.put(".", "\\."); 
} 

Answer 2

我想：

而不是

private final static Map<CharSequence, CharSequence> ESCAPE_MAP = new HashMap<>();{ 
     ESCAPE_MAP.put("\\", "\\\\"); 
     ESCAPE_MAP.put(".", "\\."); 
    } 

你可以写成：

private final static Map<CharSequence, CharSequence> ESCAPE_MAP = new HashMap<CharSequence, CharSequence>() { 
     { 
      put("\\", "\\\\"); 
      put(".", "\\."); 
     } 
    };