当十六进制有3位数
时,将十六进制转换为字符时出现问题我有两种方法可以在十进制值127
上转义和转换字符 转义test\\b8
时生成 test¸
unescape执行以下操作:
for (int i=0, n=node.length; i<n; i++) {
if(c == "\\"){
char c2 = node[i + 1];
char c3 = node[i + 2];
int i= Integer.parseInt(str,16);
char c = (char)i;
System.out.println("Char is:=" + c);
}
}
输出 - test¸
正如您所看到的,我将斜杠后的前两个字符转换为char。一切正常。但是,有时候字符有3个十六进制数字(例如test\\2d8
。这应该是test˘
)。当这进入我的unescape方法时,不会使用全部3个字符。只有前2个,因此产生了错误的结果。
有没有办法确定何时转换2或3个字符
答案 0 :(得分:0)
这就是我要做的事情:
String raw = new String(node); // might be a better way to get a string from the chars
int slashPos = raw.indexOf('\\');
if(slashPos >= 0) {
String hex = raw.substring(slashPos + 1);
int value = Integer.parseInt(hex,16);
}
通过这种方式,我们并不特别为2,3,4或100位数设置任何东西(尽管我确定100位数会引发异常:-))。相反,我们将协议用作字符串中的“里程碑”,然后只接受斜杠之后的所有内容都是十六进制字符串。
class HexParse {
private static class HexResult {
final boolean exists;
final int value;
HexResult(boolean e, int v) { exists = e; value = v; }
}
private final String raw;
private final HexResult result;
public HexParse(String raw) {
this.raw = raw;
int slashPos = raw.indexOf('\\');
boolean noSlash = slashPos < 0;
boolean noTextAfterSlash = slashPos > raw.length() - 2;
if(noSlash || noTextAfterSlash) {
result = new HexResult(false,0);
} else {
// throws exception if second part of string contains non-hex chars
result = new HexResult(true,Integer.parseInt(raw.substring(slashPos + 1),16));
}
}
public String toString() {
StringBuilder sb = new StringBuilder();
sb.append(raw).append(" ");
if(result.exists) {
sb.append("has hex of decimal value ").append(result.value);
} else {
sb.append("has no hex");
}
return sb.toString();
}
public static void main(String...args) {
System.out.println(new HexParse("test`hello")); // none
System.out.println(new HexParse("haha\\abcdef")); // hex
System.out.println(new HexParse("good\\f00d")); // hex
System.out.println(new HexParse("\\84b")); // hex
System.out.println(new HexParse("\\")); // none
System.out.println(new HexParse("abcd\\efgh")); //exception
}
}
c:\files\j>javac HexParse.java
c:\files\j>java HexParse
test`hello has no hex
haha\abcdef has hex of decimal value 11259375
good\f00d has hex of decimal value 61453
\84b has hex of decimal value 2123
\ has no hex
Exception in thread "main" java.lang.NumberFormatException: For input string: "e
fgh"
at java.lang.NumberFormatException.forInputString(NumberFormatException.
java:48)
at java.lang.Integer.parseInt(Integer.java:458)
at HexParse.<init>(HexParse.java:21)
at HexParse.main(HexParse.java: