public char[] charArray(int minCapacity) {
        final char[] charArray = this.charArray;
        if (charArray.length >= minCapacity) {
            return charArray;
        }
        return allocateCharArray(minCapacity);
    }
Returns a thread-local character array whose length is equal to or greater than the specified
{@code minCapacity}.
core/src/main/java/com/linecorp/armeria/internal/common/util/TemporaryThreadLocals.java