How To Read Edi Raw Data

virtual data

Larn more nearly reading EDI data in this Java tutorial.

These days, most Java developers look to bargain with JSON to substitution data with other systems and businesses. Nevertheless, what happens when JSON is not an pick? It's piece of cake to forget that in that location are other formats for data commutation, some of which are more hard to handle. One such format is known as EDI. EDI itself comes in several flavors — for example, X12 and EDIFACT — so code to read it may not always exist "ane size fits all."

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On the surface, reading EDI data seems to be a simple effort. A programmer may see a sample file and attempt to read it using the basic string parsing APIs available in his or her programming language's standard library. Unfortunately, this may not always work and information technology becomes difficult to do data validation and handle the structure of the document effectively.

What Is EDI? An Introduction

EDI is a general term that covers several standard data formats for exchanging data between businesses (or any two parties). Ii of the about ordinarily used standards are X12 and EDIFACT. Both of these standards correspond information in a sequence of named segments (which are basically records containing individual fields). For example, a simple segment might look like this:

SEG*SMITH*JOHN*20190101~

In this example, the name of the segment is "SEG", and it contains iii fields — ii strings and a date. Each field (known as an chemical element) is separated from the others past the delimiter * (asterisk), and the end of the segment is indicated with the delimiter ~ (tilde).

EDI also has a structure similar to XML or JSON where segments are nested within begin/end boundaries known as loops. In the example, the X12 acknowledgment exchange is shown below; the indentation is added to emphasize the structure. Notwithstanding, in practice, the construction is not apparent by looking at an unformatted EDI file.

          ISA*00*          *00*          *ZZ*Receiver       *ZZ*Sender         *191031*1301*^*00501*000000001*0*P*:~   GS*FA*ReceiverDept*SenderDept*20191031*130123*000001*X*005010X230~     ST*997*0001~       AK1*HC*000001~         AK2*837*0001~           AK3*NM1*eight**8~           AK4*eight*66*7*MI~         AK5*R*five~       AK9*R*1*1*0~     SE*8*0001~   GE*ane*000001~ IEA*ane*000000001~

Reading EDI equally a Stream of Events

One option for reading EDI is to process the data as a stream of events. The StAEDI (pronounced "steady") Coffee library takes the same approach for EDI that the standard Java StAX API takes for processing XML — a stream of events. A simple program that but lists the names of the segments could look something similar this:

            EDIInputFactory manufactory = EDIInputFactory.newFactory(); InputStream stream = new FileInputStream("my_edi_file.txt"); EDIStreamReader reader = factory.createEDIStreamReader(stream); EDIStreamEvent event;  while (reader.hasNext()) {   event = reader.next();    if (event == EDIStreamEvent.START_SEGMENT) {     System.out.println("Segment: " + reader.getText());   } }

If you are familiar with the StAX API for XML, this should wait familiar. The EDIStreamReader is used in a loop similar to an iterator or a database upshot ready. Each call to the next method will render the side by side data event from the EDI file. In addition to events for the starting time of a segment, there are events for handling:

First and cease of an interchange (ISA /IEA in X12,UNB /UNZ for EDIFACT)
Beginning and end of a message grouping (GS /GE in X12,UNG /UNE for EDIFACT)
Showtime and finish of a transaction (ST /SE in X12,UNH /UNT for EDIFACT)
Beginning and cease of a loop (depending on configuration)
Start and cease of a segment
Beginning and end of a composite chemical element
Private data elements
Segment errors
Data element errors

What About Structure and Validation?

Processing EDI using StAEDI volition give you only basic structure and validation (interchange, group, and transaction envelop structures). If yous need to handle the construction and validation of the information within a transaction (and you probably exercise), a schema must be provided. A schema is loosely based on standard XML schema syntax and provides details on the order of segments and elements in your transaction. Additionally, constraints may be placed on the length and data type of elements.

An EDI schema for the example X12997 transaction above could be defined using the following XML. Thetransaction chemical element and its sub-elements ascertain the structure of the transaction. Each segment referencessegmentType elements defined below, and eachsegmentType referenceselementType s andcompositeType s as necessary. Enumerated values foridentifier element types accept been generally omitted for brevity.

            <schema xmlns="http://xlate.io/EDISchema/v2">   <transaction>     <sequence>       <segment ref="AK1" minOccurs="one" />       <loop code="2000" maxOccurs="999999">         <sequence>           <segment ref="AK2" />           <loop code="2100" maxOccurs="999999">             <sequence>               <segment ref="AK3" />               <segment ref="AK4" maxOccurs="99" />             </sequence>           </loop>           <segment ref="AK5" minOccurs="1" />         </sequence>       </loop>       <segment ref="AK9" minOccurs="1" />     </sequence>   </transaction>    <elementType name="E0002" number="two" base="numeric" maxLength="6" />   <elementType name="E0028" number="28" base of operations="numeric" maxLength="9" />   <elementType proper noun="E0097" number="97" base of operations="numeric" maxLength="6" />   <elementType proper name="E0123" number="123" base="numeric" maxLength="half-dozen" />   <elementType name="E0143" number="143" base="identifier" minLength="three" maxLength="three" />   <elementType name="E0329" number="329" base of operations="string" minLength="4" maxLength="ix" />   <elementType name="E0447" number="447" base="string" maxLength="4" />   <elementType proper noun="E0479" number="479" base="identifier" minLength="2" maxLength="ii" />   <elementType name="E0480" number="480" base="string" maxLength="12" />   <elementType name="E0715" number="715" base="identifier">     <enumeration>       <value>A</value>       <value>E</value>       <value>M</value>       <value>P</value>       <value>R</value>       <value>W</value>       <value>X</value>     </enumeration>   </elementType>   <elementType proper name="E0716" number="716" base="identifier" maxLength="iii" />   <elementType name="E0717" number="717" base="identifier">     <enumeration>       <value>A</value>       <value>East</value>       <value>M</value>       <value>R</value>       <value>W</value>       <value>X</value>     </enumeration>   </elementType>   <elementType name="E0718" number="718" base="identifier" maxLength="3" />   <elementType name="E0719" number="719" base of operations="numeric" maxLength="10" />   <elementType name="E0720" number="720" base="identifier" maxLength="3" />   <elementType name="E0721" number="721" base of operations="cord" minLength="2" maxLength="3" />   <elementType proper noun="E0722" number="722" base="numeric" maxLength="2" />   <elementType name="E0723" number="723" base of operations="identifier" maxLength="three" />   <elementType name="E0724" number="724" base="string" maxLength="99" />   <elementType proper noun="E0725" number="725" base="numeric" maxLength="4" />   <elementType name="E1528" number="1528" base="numeric" maxLength="2" />   <elementType name="E1686" number="1686" base="numeric" maxLength="four" />   <elementType name="E1705" number="1705" base="cord" maxLength="35" />   <compositeType name="C030">     <sequence>       <element ref="E0722" minOccurs="1" />       <chemical element ref="E1528" />       <element ref="E1686" />     </sequence>   </compositeType>   <segmentType name="AK1">     <sequence>       <element ref="E0479" minOccurs="1" />       <chemical element ref="E0028" minOccurs="one" />       <element ref="E0480" />     </sequence>   </segmentType>   <segmentType proper name="AK2">     <sequence>       <chemical element ref="E0143" minOccurs="i" />       <element ref="E0329" minOccurs="1" />       <chemical element ref="E1705" />     </sequence>   </segmentType>   <segmentType name="AK3">     <sequence>       <element ref="E0721" minOccurs="one" />       <element ref="E0719" minOccurs="ane" />       <element ref="E0447" />       <element ref="E0720" />     </sequence>   </segmentType>   <segmentType proper noun="AK4">     <sequence>       <composite ref="C030" minOccurs="1" />       <element ref="E0725" />       <chemical element ref="E0723" minOccurs="1" />       <element ref="E0724" />     </sequence>   </segmentType>   <segmentType proper name="AK5">     <sequence>       <element ref="E0717" minOccurs="one" />       <element ref="E0718" />       <element ref="E0718" />       <chemical element ref="E0718" />       <element ref="E0718" />       <chemical element ref="E0718" />     </sequence>   </segmentType>   <segmentType name="AK9">     <sequence>       <element ref="E0715" minOccurs="1" />       <element ref="E0097" minOccurs="i" />       <chemical element ref="E0123" minOccurs="1" />       <element ref="E0002" minOccurs="ane" />       <element ref="E0716" />       <element ref="E0716" />       <element ref="E0716" />       <element ref="E0716" />       <element ref="E0716" />     </sequence>   </segmentType> </schema>

Using a schema while parsing an EDI file is direct-frontwards. As the program iterates over the outcome stream, the awarding code must provide a Schema object at the showtime of a transaction. (before end of segment)

            EDIInputFactory factory = EDIInputFactory.newFactory(); InputStream stream = new FileInputStream("my_edi_file.txt"); EDIStreamReader reader = factory.createEDIStreamReader(stream);  while (reader.hasNext()) {   EDIStreamEvent event = reader.next();    if (event == EDIStreamEvent.START_TRANSACTION) {     SchemaFactory schemaFactory = SchemaFactory.newFactory();     Schema txSchema = schemaFactory.createSchema(new FileInputStream("my_edi_schema.xml"));     reader.setTransactionSchema(txSchema);   } else {     // Practise something else with the consequence   } }

Summary

Are you writing custom code to process EDI information in Java? Have you tried StAEDI and encountered an event? Give your feedback in the comments, or open an outcome on the StAEDI GitHub repository.