SpringBoot源码学习系列之@PropertySource注解实现

private void load0 (LineReader lr) throws IOException {
        char[] convtBuf = new char[1024];
        int limit;
        // 当前key所在位置
        int keyLen;
        // 当前value所在位置
        int valueStart;
        char c;//读取的字符
        boolean hasSep;
        boolean precedingBackslash;//是否转义字符，eg:/n etc.
		// 一行一行地读取
        while ((limit = lr.readLine()) >= 0) {
            c = 0;
            keyLen = 0;
            valueStart = limit;
            hasSep = false;

            //System.out.println("line=<" + new String(lineBuf, 0, limit) + ">");
            precedingBackslash = false;
            //key的长度小于总的字符长度，那么就进入循环
            while (keyLen < limit) {
                c = lr.lineBuf[keyLen];
                //need check if escaped.
                if ((c == '=' ||  c == ':') && !precedingBackslash) {
                    valueStart = keyLen + 1;
                    hasSep = true;
                    break;
                } else if ((c == ' ' || c == '\t' ||  c == '\f') && !precedingBackslash) {
                    valueStart = keyLen + 1;
                    break;
                }
                if (c == '\\') {
                    precedingBackslash = !precedingBackslash;
                } else {
                    precedingBackslash = false;
                }
                keyLen++;
            }
            //value的起始位置小于总的字符长度，那么就进入该循环
            while (valueStart < limit) {
                c = lr.lineBuf[valueStart];
                //当前字符是否非空格类字符
                if (c != ' ' && c != '\t' &&  c != '\f') {
                    if (!hasSep && (c == '=' ||  c == ':')) {
                        hasSep = true;
                    } else {
                        break;
                    }
                }
                valueStart++;
            }
            //读取key
            String key = loadConvert(lr.lineBuf, 0, keyLen, convtBuf);
            //读取value
            String value = loadConvert(lr.lineBuf, valueStart, limit - valueStart, convtBuf);
            put(key, value);
        }
    }