cdm/src/main/java/ucar/nc2/NetcdfFileWriter.java
public boolean addVariableAttribute(Variable v, Attribute att) {
    if (!defineMode)
      throw new UnsupportedOperationException("not in define mode");

    if (!isValidObjectName(att.getShortName())) {
      String attName = createValidObjectName(att.getShortName());
      log.warn("illegal netCDF-3 attribute name= " + att.getShortName() + " change to " + attName);
      att = new Attribute(attName, att.getValues());
    }

    v.addAttribute(att);
    return true;
  }
public boolean addVariableAttribute(Variable v, Attribute att) {
    if (!defineMode)
      throw new UnsupportedOperationException("not in define mode");

    if (!isValidObjectName(att.getShortName())) {
      String attName = createValidObjectName(att.getShortName());
      log.warn("illegal netCDF-3 attribute name= " + att.getShortName() + " change to " + attName);
      att = new Attribute(attName, att.getValues());
    }

    v.addAttribute(att);
    return true;
  }
public boolean addVariableAttribute ( Variable v , Attribute att ) { if ( ! defineMode ) throw new UnsupportedOperationException ( "not in define mode" ) ; if ( ! isValidObjectName ( att . getShortName ( ) ) ) { String attName = createValidObjectName ( att . getShortName ( ) ) ; log . warn ( "illegal netCDF-3 attribute name= " + att . getShortName ( ) + " change to " + attName ) ; att = new Attribute ( attName , att . getValues ( ) ) ; } v . addAttribute ( att ) ; return true ; }
Add an attribute to the named Variable. Must be in define mode.

@param v   Variable to add attribute to
@param att Attribute to add.
@return true if attribute was added, false if not allowed by CDM.
Add an attribute to the named Variable . Must be in define mode .