java转义括号

Question

我有这个小类来对字符串进行多次替换:

import java.util.HashMap;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
import org.apache.commons.lang.StringUtils;
public class MultipleReplace {
    public static void main(String[] args) {
        Map<String,String> tokens = new HashMap<String,String>();
        tokens.put(":asd:", "<img src=asd.gif>");
        tokens.put(":)", "<img src=sorriso.gif>");
        String template = ":asd: bravo! :)";
        String patternString = "(" + StringUtils.join(tokens.keySet(), "|") + ")";
        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(template);
        StringBuffer sb = new StringBuffer();
        while(matcher.find()) {
            matcher.appendReplacement(sb, tokens.get(matcher.group(1)));
        }
        matcher.appendTail(sb);

        System.out.println(sb.toString());
    }
}

问题是在第二次替换,我有一个括号导致:

线程"main"中的异常java.util.regex.PatternSyntaxException:索引8(:)|:asd :)附近的不匹配的结束')'

我怎么能逃脱括号？或者,你能建议一个替代方案来做多次替换吗？

非常感谢,对不起我的英语:)

编辑:

使用反斜杠转义')'也不起作用,它不会编译:

"无效的转义序列(有效转义序列为\ b\t \n\f\r \"\'\)"

新编辑

使用两个反斜杠编译,但不做替换.

最后的编辑

最后找到了解决方案,在构建模式时使用Pattern.quote.必须使用迭代器来完成循环.

这里是正确的代码:

package string;
import java.util.HashMap;
import java.util.Iterator;
import java.util.Map;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
public class MultipleReplace {
    @SuppressWarnings("rawtypes")
    public static void main(String[] args) {
        Map<String,String> tokens = new HashMap<String,String>();
        tokens.put(":asd:", "<img src=asd.gif>");
        tokens.put(":)", "<img src=sorriso.gif>");
        String template = ":asd: bravo! :)";
        Iterator it = tokens.entrySet().iterator();
        String patternString = "(";
        while (it.hasNext()) {
            Map.Entry pairs = (Map.Entry)it.next();
            System.out.println(pairs.getKey() + " = " + pairs.getValue());
            patternString = patternString +Pattern.quote((String) pairs.getKey());
            if (it.hasNext())
            {
                patternString = patternString + "|";
            }
        }
        patternString = patternString + ")";
        System.out.println(patternString);
        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(template);
        StringBuffer sb = new StringBuffer();
        while(matcher.find()) {
            matcher.appendReplacement(sb, tokens.get(matcher.group(1)));
        }
        matcher.appendTail(sb);
        System.out.println(sb.toString());
    }
}

如果我可以改进工作,请评论它!非常感谢你!

Answer 1

使用Pattern.quote就像我在评论中写的那样.它适用于每个字符串,对于包含大量非字母数字字符的长字符串,它不易出错.

更新

这是一个闪亮的(未经测试的)Java 8解决方案:

    final Map<String, String> tokens = new HashMap<>();
    tokens.put(":asd:", "<img src=asd.gif>");
    tokens.put(":)", "<img src=sorriso.gif>");
    final String template = ":asd: bravo! :)";

    final String patternString = tokens.keySet()
        .stream().map(Pattern::quote).collect(Collectors.joining("|"));
    final Pattern pattern = Pattern.compile(patternString);
    final Matcher matcher = pattern.matcher(template);
    final StringBuffer sb = new StringBuffer();
    while (matcher.find()) {
        matcher.appendReplacement(sb, tokens.get(matcher.group(0)));
    }
    matcher.appendTail(sb);
    System.out.println(sb.toString());

Answer 2

使用反斜杠:\).必须转义Parens,因为它们可用于对正则表达式的部分进行分组.

    String template = ":asd: bravo\\! :\\)";