一个替换java字符串中${}或者{}等占位符的工具类

/**
 * 一个替换java字符串中${}或者{}等占位符的工具类
 *
 * @date 2018/5/31
 */
public class ParserUtils {
    /**
     * 将字符串text中由openToken和closeToken组成的占位符依次替换为args数组中的值
     *
     * @param openToken
     * @param closeToken
     * @param text
     * @param args
     * @return
     */
    public static String parse(String openToken, String closeToken, String text, Object... args) {
        if (args == null || args.length <= 0) {
            return text;
        }
        int argsIndex = 0;

        if (text == null || text.isEmpty()) {
            return "";
        }
        char[] src = text.toCharArray();
        int offset = 0;
        // search open token
        int start = text.indexOf(openToken, offset);
        if (start == -1) {
            return text;
        }
        final StringBuilder builder = new StringBuilder();
        StringBuilder expression = null;
        while (start > -1) {
            if (start > 0 && src[start - 1] == '\') {
                // this open token is escaped. remove the backslash and continue.
                builder.append(src, offset, start - offset - 1).append(openToken);
                offset = start + openToken.length();
            } else {
                // found open token. let's search close token.
                if (expression == null) {
                    expression = new StringBuilder();
                } else {
                    expression.setLength(0);
                }
                builder.append(src, offset, start - offset);
                offset = start + openToken.length();
                int end = text.indexOf(closeToken, offset);
                while (end > -1) {
                    if (end > offset && src[end - 1] == '\') {
                        // this close token is escaped. remove the backslash and continue.
                        expression.append(src, offset, end - offset - 1).append(closeToken);
                        offset = end + closeToken.length();
                        end = text.indexOf(closeToken, offset);
                    } else {
                        expression.append(src, offset, end - offset);
                        // offset = end + closeToken.length()
                        break;
                    }
                }
                if (end == -1) {
                    // close token was not found.
                    builder.append(src, start, src.length - start);
                    offset = src.length;
                } else {
                    ///////////////////////////////////////仅仅修改了该else分支下的个别行代码////////////////////////

                    String value = argsIndex <= args.length - 1 ?
                        (args[argsIndex] == null ? "" : args[argsIndex].toString()) : expression.toString();
                    builder.append(value);
                    offset = end + closeToken.length();
                    // argsIndex++;
                    ////////////////////////////////////////////////////////////////////////////////////////////////
                }
            }
            start = text.indexOf(openToken, offset);
        }
        if (offset < src.length) {
            builder.append(src, offset, src.length - offset);
        }
        return builder.toString();
    }

    public static String parse0(String text, Object... args) {
        return ParserUtils.parse("${", "}", text, args);
    }

    public static String parse1(String text, Object... args) {
        return ParserUtils.parse("{", "}", text, args);
    }
}

上面这种比较复杂。我自己写了一个

替换/user/{username}/{name} ------>/user/{}/{}的方法

protected static String getChangedString(String str) {
        char[] chars = str.toCharArray();
        Boolean isAppend = true;
        StringBuffer stringBuffer = new StringBuffer();
        for (int i = 0; i < chars.length; i++) {
            char currentChar = chars[i];
            if (isAppend) {
                if (currentChar == '{') {
                    isAppend = false;
                }
                stringBuffer.append(chars[i]);
            } else {
                if (currentChar == '}') {
                    isAppend = true;
                    stringBuffer.append(chars[i]);
                }
            }
        }
        return stringBuffer.toString();
    }