FIX Message

Create

A message can be created in two different ways:

1. Create a skeleton and set fields
2. Parse a raw FIX message (byte array)

To create a framework for a FIX application-level message, use the FIXFieldList constructor. Thereafter you can set the desired field values of a message and send it to the counter-party. In general FIXFieldList is just a List <FIXField> so it contains all the methods from java.util.List plus a few convenient methods to manipulate tags and groups of tags.

For example:

FIXFieldList messageContent = new FIXFieldList();
messageContent.addTag(148, "Hello there");

To parse a string containing a raw FIX message into the FIXMessage class, use the RawFIXUtil.getFIXFieldList(byte[]) method.

For example:

byte[] bytes =
"8=FIX.4.3\u00019=94\u000135=A\u000149=target\u000156=sender\u0001115=onBehalf\u000134=1\u000150=senderSub" +
"\u000152=20080212-04:15:18.308\u000198=0\u0001108=600\u000110=124\u0001".getBytes();

FIXFieldList msg = RawFIXUtil.getFIXFieldList(bytes);

Get field

To get a FIX field value, use the FIXFieldList.getTagValueAsXXX(int tag) methods. For example, if you need a string
value please use FIXFieldList.getTagValueAsString(int tag), if you need int - FIXFieldList.getTagValueAsInt(int
tag), etc.

Please pay attention that FIXFieldList.getTagValueAsString(int tag) and FIXFieldList.getTagValueAsBytes(int tag)
return a null if this tag is not present in message. The rest methods for accessing value as primitive type throw
an FieldNotFoundException if there is no such tag.

Add field

To add a field to message please use a set of FIXFieldList.addTag() methods with different parameters.

Set field

To change a field value please use FIXFieldList.set() methods:

message.set(148, "Hello there");

Note: the tag will be added to the message if such tag is absent.

Remove field

To remove a field by tag, use the FIXFieldList.removeTag(int tag) method. This method returns "true" if the given
tag is found and the field is
removed. Otherwise the method returns "false".

message.removeTag(148);

Repeating group

To get a value from repeating group use FIXFieldList.getTagValueAsXXX(int tag, int occurrence)
Example:

FIXFieldList messageContent = new FIXFieldList(); // prepare message
messageContent.addTag(148, "Hello there"); // Add Subject
messageContent.addTag(33, 3); // Add Repeating group
messageContent.addTag(58, "line1");
messageContent.addTag(58, "line2");
messageContent.addTag(58, "line3");

System.out.println(messageContent.getTagValueAsString(58, 2));

another more convenient option is to use FIXFieldList.split(int leadingTagNumber)

FIXFieldList messageContent = new FIXFieldList(); // prepare message
messageContent.addTag(148, "Hello there"); // Add Subject
messageContent.addTag(33, 3); // Add Repeating group
messageContent.addTag(58, "line1");
messageContent.addTag(58, "line2");
messageContent.addTag(58, "line3");

List
<FIXFieldList> repeatingGroups= messageContent.split(58);
    // we have a list of 3 groups and each group in our case
    // contains a repeating group with single 58 tag.
    for (FIXFieldList repeatingGroup:repeatingGroups){
    System.out.println(repeatingGroup.getTagValueAsString(58)); // line1 line2 line3
    }

User defined fields

User Defined Fields (tag numbers from 5000 to 9999) are handled like ordinary fields.

For example:

int theCustomTag = 5000; // reserved for user defined fields
// generates a new FIX message
FIXFieldList messageContent = new FIXFieldList();
messageContent.addTag(theCustomTag, "0.15"); // sets the tag value

Clone message

    To clone a FIX message, use the FIXFieldList.clone() method.