monitorTarget.append(buf, "key1", () -> "value1");
        buf.append(",");
        monitorTarget.append(buf, "key2", () -> 123);
        buf.append(",");
        monitorTarget.append(buf, "key3", () -> null);

        assertEquals("\"key1\":\"value1\",\"key2\":123,\"key3\":null", buf.toString());
    }

    // Test append with empty string
    public void test_append_emptyString() {

            if (values == null) {
                // nothing
            } else if (values.length == 1) {
                queryBuf.append(' ').append(key).append(":\"").append(values[0]).append('\"');
            } else if (values.length > 1) {
                boolean first = true;
                queryBuf.append(" (");
                for (final String value : values) {
                    if (first) {
                        first = false;

        buf.append("{\"text\":\"");
        buf.append(LF);
        buf.append(StringEscapeUtils.escapeJson(discloser.getSavedSubject().orElse(StringUtil.EMPTY).trim()));
        buf.append(LF).append("```");
        buf.append(LF).append(StringEscapeUtils.escapeJson(discloser.getSavedPlainText().orElse(StringUtil.EMPTY).trim()));
        buf.append(LF).append("```\"}");
        return buf.toString();
    }

        }

        buffer.append("----------").append(LS);

        int size = artifacts.size();

        buffer.append(size).append(" required artifact");

        if (size > 1) {
            buffer.append("s are");
        } else {
            buffer.append(" is");
        }

        buffer.append(" missing.").append(LS).append(LS).append("for artifact: ");

        StringBuilder sb = new StringBuilder();
        sb.append(dm).append(createdBy);
        sb.append(dm).append(createdTime);
        sb.append(dm).append(name);
        sb.append(dm).append(sortOrder);
        sb.append(dm).append(updatedBy);
        sb.append(dm).append(updatedTime);
        sb.append(dm).append(value);
        if (sb.length() > dm.length()) {
            sb.delete(0, dm.length());

        switch (errorClass) {
        case SUCCESS:
            result.append("SUCCESS");
            break;
        case ERR_NAM_SRVC:
            result.append("ERR_NAM_SRVC/");
            switch (errorCode) {
            case FMT_ERR:
                result.append("FMT_ERR: Format Error");
            default:
                result.append("Unknown error code: ").append(errorCode);
            }
            break;

		// string "ID"
		o = append(o, 0xa2, 0x49, 0x44)
		o = msgp.AppendBytes(o, (z.VersionID)[:])
		// string "DDir"
		o = append(o, 0xa4, 0x44, 0x44, 0x69, 0x72)
		o = msgp.AppendBytes(o, (z.DataDir)[:])
		// string "EcAlgo"
		o = append(o, 0xa6, 0x45, 0x63, 0x41, 0x6c, 0x67, 0x6f)
		o = msgp.AppendUint8(o, uint8(z.ErasureAlgorithm))
		// string "EcM"
		o = append(o, 0xa3, 0x45, 0x63, 0x4d)

        builder.append("type:").append(getType());
        builder.append('{');

        Iterator<Map.Entry<String, RequirementMatcher>> providesIter =
                provides.entrySet().iterator();
        while (providesIter.hasNext()) {
            Map.Entry<String, RequirementMatcher> provideEntry = providesIter.next();

        sb.append(dm).append(createdBy);
        sb.append(dm).append(createdTime);
        sb.append(dm).append(generator);
        sb.append(dm).append(path);
        sb.append(dm).append(target);
        sb.append(dm).append(thumbnailId);
        if (sb.length() > dm.length()) {
            sb.delete(0, dm.length());
        }
        sb.insert(0, "{").append("}");
        return sb.toString();

        buf.append(File.separator);
        buf.append(getExecuteType());
        buf.append(File.separator);
        buf.append("resources");
        buf.append(cpSeparator);
        // WEB-INF/classes
        buf.append("WEB-INF");
        buf.append(File.separator);
        buf.append("classes");
        // target/classes
        final String userDir = System.getProperty("user.dir");