tempBuf.append(Arrays.toString((double[]) value));
            } else {
                tempBuf.append('"').append(StringEscapeUtils.escapeJson(value.toString())).append('"');
            }
        } catch (final Exception e) {
            tempBuf.append("null");
        }
        buf.append(tempBuf.toString());
        return buf;
    }

    /**
     * Appends a timestamp to the buffer.
     *

            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;

    }

    // Test multiple appends to the same buffer
    @Test
    public void test_multipleAppends() {
        StringBuilder buf = new StringBuilder();

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

        buf.append("-Xlog:gc*,gc+age=trace,safepoint:file=");
        if (logFilePath != null) {
            buf.append(logFilePath);
        } else {
            buf.append(ComponentUtil.getSystemHelper().getLogFilePath());
        }
        buf.append(File.separator);
        buf.append("gc-").append(getExecuteType()).append(".log");
        buf.append(":utctime,pid,tags:filecount=5,filesize=64m");

            } catch (final Exception e) {
                final StringBuilder buf = createStringBuffer(keyObj, getCurrentTimeMillis());
                buf.append('\t').append("action:begin");
                buf.append('\t').append("error:").append(escapeValue(e.getLocalizedMessage()).replaceAll("\\s", " "));
                log(buf);
            }
        });
    }

    /**

     * @param chain the existing filter chain to append to
     * @return a new filter chain that includes the appended filter
     */
    protected FilterChain appendFilterChain(final Filter filter, final FilterChain chain) {
        return (context, query, boost) -> filter.execute(context, query, boost, chain);
    }

    /**
     * Creates the default filter chain that executes query commands.

        final StringBuilder buf = new StringBuilder(100);
        buf.append("/WEB-INF/view/").append(page);
        if (StringUtil.isNotBlank(lang)) {
            buf.append('_').append(lang);
            if (StringUtil.isNotBlank(country)) {
                buf.append('_').append(country);
            }
        }
        buf.append(".jsp");
        return buf.toString();
    }

    /**

                    logger.debug("[EXPORT] Processing: count={}", currentCount);
                }
                return true;
            });
            resultBuf.append("Exported ").append(count).append(" documents.");
            if (logger.isInfoEnabled()) {
                logger.info("[EXPORT] Completed: exportedCount={}, elapsedTime={}ms", count, System.currentTimeMillis() - startTime);
            }

        if (v.startsWith("^")) {
            buf.append(v);
            if (!v.endsWith("$")) {
                buf.append(".*");
            }
        } else if (v.endsWith("$")) {
            buf.append(".*");
            buf.append(v);
        } else if (v.endsWith("/\\E")) {
            buf.append(".*");
            buf.append(v);
            buf.append(".*");
        } else {
            buf.append(v);

        final StringBuilder buf = new StringBuilder((int) (content.length() * 1.3));
        buf.append(prefix).append(1).append(':').append(values[0]);
        for (int i = 1; i < values.length; i++) {
            buf.append('\n').append(prefix).append(i + 1).append(':').append(values[i]);
        }
        return buf.toString();
    }