@Override
    public void copyFrom(final LongText source) {
        this.text = source.text;
    }
LongText represents a string field, but the length is not predictable and could be longer than 1000.
This is a wrapper of Java String only, which provides an indicator of long text field.
oap-server/server-core/src/main/java/org/apache/skywalking/oap/server/core/analysis/record/LongText.java