Develop Reference

Initialize multiple numeric fields at once in JAVA that begin with certain values

I am working on a Java class that contains a ton of numeric fields. Most of them would begin with something like 'CMTH' or 'FYTD'. Is it possible to initialize all fields of the same type that begin or end with a certain value. For example I have the following fields:
CMthRepCaseACR CMthRepUnitACR CMthRecCaseACR CMthRecUnitACR CMthHecCaseACR CMthHecUnitACR FYTDHecCaseACR FYTDHecUnitACR CMthBBKCaseACR CMthBBKUnitACR CMthPIHCaseACR .
I am trying to figure if it is possible to initialize all fields to zero that end with an 'ACR' or begin with an 'Cmth"
I know I can do something like cmtha = cmthb = cmthc = 0 but I was wondering there was a command where you can some kind of mask to initialize
Thanks

Assuming that you cannot change that said Java class (and e.g. use a collection or map to store the values) your best bet is probably reflection (see also: Trail: The Reflection API). Reflection gives you access to all fields of the class and you can then implement whatever matching you'd like.
Here's a short demo to get you started, minus error handling, sanity checks and adaptions to your actual class:
import java.util.stream.Stream;
public class Demo {
private static class DemoClass {
private int repCaseACR = 1;
private int CMthRepUnit = 2;
private int foo = 3;
private int bar = 4;
#Override
public String toString() {
return "DemoClass [repCaseACR=" + repCaseACR + ", CMthRepUnit=" + CMthRepUnit + ", foo=" + foo + ", bar="
+ bar + "]";
}
}
public static void main(String[] args) {
DemoClass demoClass = new DemoClass();
System.out.println("before: " + demoClass);
resetFields(demoClass, "CMth", null);
System.out.println("after prefix reset: " + demoClass);
resetFields(demoClass, null, "ACR");
System.out.println("after suffix reset: " + demoClass);
}
private static void resetFields(DemoClass instance, String prefix, String suffix) {
Stream.of(instance.getClass().getDeclaredFields())
.filter(field ->
(prefix != null && field.getName().startsWith(prefix))
|| (suffix != null && field.getName().endsWith(suffix)))
.forEach(field -> {
field.setAccessible(true);
try {
field.set(instance, 0);
} catch (IllegalArgumentException | IllegalAccessException e) {
// TODO handle me
}
});
}
}
Output:
before: DemoClass [repCaseACR=1, CMthRepUnit=2, foo=3, bar=4]
after prefix reset: DemoClass [repCaseACR=1, CMthRepUnit=0, foo=3, bar=4]
after suffix reset: DemoClass [repCaseACR=0, CMthRepUnit=0, foo=3, bar=4]
Note: Both links are seriously dated but the core functionality of reflection is still the same.

Java ternary operator badly evaluating null

I had a weird situation today while I was writing tests. Basically, I had a class with data. Let's say Toy for example, from which we can retrieve a name:
public class Toy {
private String name;
public Toy(String name) {
this.name = name;
}
public String getName() {
return name;
}
}
And I had an exception, which was working in a way similar to this (e.g. just displaying data about all the objects on which we were working before it went bad); I also included a main for test purpose:
public class ToyFactoryException extends Exception {
public ToyFactoryException(Toy firstToy, Toy secondToy) {
super("An error occurred when manufacturing: " +
"\nfirstToy: " + firstToy != null ? firstToy.getName() : null +
"\nsecondToy: " + secondToy != null ? secondToy.getName() : null);
}
public static void main(String[] args) {
try {
throw new ToyFactoryException(null, new Toy("hi"));
} catch (ToyFactoryException myException) {
System.out.println("It should be there.");
} catch (Exception exception) {
System.out.println("But it's there instead.");
}
}
}
As I wrote in the first catch block, the exception should be caught in the ToyFactoryException.
However, in the exception, it's trying to read firstToy.getName() right here: firstToy != null ? firstToy.getName() : null
firstToy != null should evaluate to false, which means it shouldn't be trying to call firstToy.getName() in the first place. When you write it in the reverse order:
public ToyFactoryException(Toy firstToy, Toy secondToy) {
super("An error occurred when manufacturing: " +
"\nfirstToy: " + firstToy != null ? null : firstToy.getName() +
"\nsecondToy: " + secondToy != null ? secondToy.getName() : null);
}
You realise it reads null instead now, which means it's truly reading firstToy != null as true.
If you write the main this way instead (the null is the second parameter of the constructor):
public static void main(String[] args) {
try {
throw new ToyFactoryException(new Toy("hi"), null);
} catch (ToyFactoryException myException) {
System.out.println("It should be there.");
} catch (Exception exception) {
System.out.println("But it's there instead.");
}
}
It works properly, despite the secondToy ternary condition being written the same way as the firstToy ternary.
Why is the ternary condition on firstToy not evaluating null properly?

You should put parentheses around your conditional expression.
This:
"string " + firstToy != null ? firstToy.getName() : null
means this:
("string " + firstToy) != null ? firstToy.getName() : null
You need this:
"string " + (firstToy != null ? firstToy.getName() : null)

Java continue statement not allowed in anonymous inner class

I am threading a time consuming for-loop and executing them inside N number of threads. A continue statement is throwing error
Getting the error "Continue cannot be used outside of a loop"
for (final Message m : messagelistholder.getMessage()) {
Callable<Void> tasksToExecute = new Callable<Void>() {
public Void call() {
if (guidanceonly1 == true && !QuoteUtil.isECPQuote(list.get(0))) {
String msg = "Message From " + m.getSource() + " when retrieving Guidance values: "
+ m.getDescription();
String lcladdStatusMessages = CommonUtil.getLoclizedMsg(
"PRCE_LNE_ITM_MSG_FRM_WHN_RETRVNG_GUIDNCE_VAL",
new String[]{m.getSource(), m.getDescription()}, msg);
list.get(0).addStatusMessages("Info", lcladdStatusMessages);
} else if ("Error".equalsIgnoreCase(m.getSeverity())) {
if (m.getCode().indexOf("_NF") > 0) {
continue; // price not found due to private sku
}
if ("Eclipse".equalsIgnoreCase(m.getSource())) {
String msg1 = "Please check Sold To customer data. ";
String lcladdStatusMessages1 = CommonUtil
.getLoclizedMsg("PRCE_LNE_ITM_PLS_CHK_SLDTO_CUST_DTA", null, msg1);
String msg2 = "Discount information may not be returned from Optimus due to "
+ m.getSeverity() + " From " + m.getSource() + " " + m.getDescription();
String lcladdStatusMessages2 = CommonUtil.getLoclizedMsg(
"PRCE_LNE_ITM_DSCNT_INFO_MNT_RTRND_FRM_OPTMS_DUETO_FRM",
new String[]{m.getSeverity(), m.getSource(), m.getDescription()}, msg2);
list.get(0).addStatusMessages(m.getSeverity(),
(m.getDescription().contains("MDCP") ? lcladdStatusMessages1 : "")
+ lcladdStatusMessages2);
} else {
if (response1.getItems() == null) {
String lcladdStatusMessages = CommonUtil.getLoclizedMsg("PRCE_LNE_ITM_OPTMS_ERR",
new String[]{m.getSource(), m.getDescription()}, m.getDescription());
list.get(0).addStatusMessages("Error", lcladdStatusMessages);
list.get(0).setOptimusError(true);
} else {
if (!QuoteUtil.isECPQuote(list.get(0))) {
String lcladdStatusMessages = CommonUtil.getLoclizedMsg(
"PRCE_LNE_ITM_MSG_FRM_WHN_RETRVNG_GUIDNCE_VAL",
new String[]{m.getSource(), m.getDescription()},
"Message From " + m.getSource() + " " + m.getDescription());
list.get(0).addStatusMessages("Info", lcladdStatusMessages);
list.get(0).setOptimusError(true);
}
}
}
}
if (list.get(0).getFlags().get(QtFlagType.ESCALATIONFORPARTNER) != null) {
list.get(0).getFlags().get(QtFlagType.ESCALATIONFORPARTNER).setFlgVl(null);
}
if (m.getCode() != null) {
String pricingServiceMsgCode = m.getCode();
String pricingServiceSeverity = m.getSeverity();
Map<Integer, AutoEscalationScenario> categoryMap;
if (StringUtils.equals("ERROR", pricingServiceSeverity)) {
categoryMap = getScenario("SEVERITY", globalAccount1, null, true, null);
if (categoryMap.size() != 0) {
finalCategorylist.get(0).putAll(categoryMap);
}
}
if (partnerExclusivityAutoEscalation1) {
categoryMap = getScenario(pricingServiceMsgCode, globalAccount1, null, true, null);
if (categoryMap != null && categoryMap.size() != 0) {
finalCategorylist.get(0).putAll(categoryMap);
}
}
}
return null;
}
};
runnableTasks.add(tasksToExecute);
}
Can someone help me to skip the particular loop for the speicified condition but without using continue statement since it throws error.

What's happening is that you are actually calling continue outside of a loop because the call() function itself does not have a for loop, so it doesn't matter if are only calling call() from a loop.
What can you do to fix this is making the call function to return a boolean and replacing the continues with return true and return false if no return true has been reached.
Then replace the:
call()
on the loop(s) for
if(call()) continue

So the I'm not saying I fully understand you code, but it appears that you are using continue to break out of that thread. On a normal multi-threaded application, it looks like you are launching multiple threads from one one loop. The continue call is inside the new thread, not the loop. As soon as you start writing the call() method, you leave the loop to run it. Looking at the code, I would try replacing continue with return. Normally I would try running it myself before I suggest it, but without the rest of the code I cannot verify that it works.

How to validate certain input parameters through a Validation API?

I have an API in which I am doing my own validation for certain input parameters. For example -
public Builder(int clientId) {
TestUtils.assertNonNegative(clientId, "ClientId");
this.clientId = clientId;
}
public Builder setUserId(String userid) {
TestUtils.assertNotNull(userid, "UserId");
this.userid = userid;
return this;
}
And my assertNonNegative and assertNotNull method in TestUtils class is like this -
public static void assertNonNegative(int val, String attr) {
if (val <= 0) {
s_logger.logError("Attribute = ", attr, " Value = ", val, " error=", attr, " cannot be negative or zero");
throw new IllegalArgumentException(attr + " cannot be negative or zero");
}
}
public static void assertNotNull(String value, String key) {
if (value == null || value.isEmpty()) {
s_logger.logError("Key = ", key, " Value = ", value, " error=", key,
" cannot be NULL or empty String");
throw new IllegalArgumentException(key + " cannot be null OR empty");
}
}
I am wondering is there any validation API available in any open source projects which I can use to substitute the above internal method I have? If yes, can anyone provide an example how would I achieve this? I still need to throw the same message back as an IllegalArgumentException

I dont understand why would you use an external API tu achieve a nullOrEmpty or a non-negative number validation but...
If you would like to verifiy an id of a user in a database directly in you Java app
This might interest you to learn:
http://www.mkyong.com/java/how-to-send-http-request-getpost-in-java/
Use a bit of PHP and verify if the user is in the database.
if(isset($_GET['idcmd']))
{
switch($_GET['idcmd'])
{
case 1:
if(isset($_POST['iduser']))
{
$sql= "SELECT idUser FROM users WHERE idUser=:iduser ";
$result = $db_conn->prepare($sql);
$result->bindParam(":iduser" ,$_POST['iduser']);
$result->execute();
$num=$result->fetchColumn();
if($num > 0){
echo "cool";
}else{
echo "nocool";
}
}
break;
}
}
Now if you make a POST request to the url www.mydomain.com/myapi.php?idcmd=1 and get the response cool, it means that the user is in database.
I hope it helps.

In Java, how do I parse an xml schema (xsd) to learn what's valid at a given element?

I'd like to be able to read in an XML schema (i.e. xsd) and from that know what are valid attributes, child elements, values as I walk through it.
For example, let's say I have an xsd that this xml will validate against:
<root>
<element-a type="something">
<element-b>blah</element-b>
<element-c>blahblah</element-c>
</element-a>
</root>
I've tinkered with several libraries and I can confidently get <root> as the root element. Beyond that I'm lost.
Given an element I need to know what child elements are required or allowed, attributes, facets, choices, etc. Using the above example I'd want to know that element-a has an attribute type and may have children element-b and element-c...or must have children element-b and element-c...or must have one of each...you get the picture I hope.
I've looked at numerous libraries such as XSOM, Eclipse XSD, Apache XmlSchema and found they're all short on good sample code. My search of the Internet has also been unsuccessful.
Does anyone know of a good example or even a book that demonstrates how to go through an XML schema and find out what would be valid options at a given point in a validated XML document?
clarification
I'm not looking to validate a document, rather I'd like to know the options at a given point to assist in creating or editing a document. If I know "I am here" in a document, I'd like to determing what I can do at that point. "Insert one of element A, B, or C" or "attach attribute 'description'".

This is a good question. Although, it is old, I did not find an acceptable answer. The thing is that the existing libraries I am aware of (XSOM, Apache XmlSchema) are designed as object models. The implementors did not have the intention to provide any utility methods — you should consider implement them yourself using the provided object model.
Let's see how querying context-specific elements can be done by the means of Apache XmlSchema.
You can use their tutorial as a starting point. In addition, Apache CFX framework provides the XmlSchemaUtils class with lots of handy code examples.
First of all, read the XmlSchemaCollection as illustrated by the library's tutorial:
XmlSchemaCollection xmlSchemaCollection = new XmlSchemaCollection();
xmlSchemaCollection.read(inputSource, new ValidationEventHandler());
Now, XML Schema defines two kinds of data types:
Simple types
Complex types
Simple types are represented by the XmlSchemaSimpleType class. Handling them is easy. Read the documentation: https://ws.apache.org/commons/XmlSchema/apidocs/org/apache/ws/commons/schema/XmlSchemaSimpleType.html. But let's see how to handle complex types. Let's start with a simple method:
#Override
public List<QName> getChildElementNames(QName parentElementName) {
XmlSchemaElement element = xmlSchemaCollection.getElementByQName(parentElementName);
XmlSchemaType type = element != null ? element.getSchemaType() : null;
List<QName> result = new LinkedList<>();
if (type instanceof XmlSchemaComplexType) {
addElementNames(result, (XmlSchemaComplexType) type);
}
return result;
}
XmlSchemaComplexType may stand for both real type and for the extension element. Please see the public static QName getBaseType(XmlSchemaComplexType type) method of the XmlSchemaUtils class.
private void addElementNames(List<QName> result, XmlSchemaComplexType type) {
XmlSchemaComplexType baseType = getBaseType(type);
XmlSchemaParticle particle = baseType != null ? baseType.getParticle() : type.getParticle();
addElementNames(result, particle);
}
When you handle XmlSchemaParticle, consider that it can have multiple implementations. See: https://ws.apache.org/commons/XmlSchema/apidocs/org/apache/ws/commons/schema/XmlSchemaParticle.html
private void addElementNames(List<QName> result, XmlSchemaParticle particle) {
if (particle instanceof XmlSchemaAny) {
} else if (particle instanceof XmlSchemaElement) {
} else if (particle instanceof XmlSchemaGroupBase) {
} else if (particle instanceof XmlSchemaGroupRef) {
}
}
The other thing to bear in mind is that elements can be either abstract or concrete. Again, the JavaDocs are the best guidance.

Many of the solutions for validating XML in java use the JAXB API. There's an extensive tutorial available here. The basic recipe for doing what you're looking for with JAXB is as follows:
Obtain or create the XML schema to validate against.
Generate Java classes to bind the XML to using xjc, the JAXB compiler.
Write java code to:
Open the XML content as an input stream.
Create a JAXBContext and Unmarshaller
Pass the input stream to the Unmarshaller's unmarshal method.
The parts of the tutorial you can read for this are:
Hello, world
Unmarshalling XML

I see you have tried Eclipse XSD. Have you tried Eclipse Modeling Framework (EMF)? You can:
Generating an EMF Model using XML Schema (XSD)
Create a dynamic instance from your metamodel (3.1 With the dynamic instance creation tool)
This is for exploring the xsd. You can create the dynamic instance of the root element then you can right click the element and create child element. There you will see what the possible children element and so on.
As for saving the created EMF model to an xml complied xsd: I have to look it up. I think you can use JAXB for that (How to use EMF to read XML file?).
Some refs:
EMF: Eclipse Modeling Framework, 2nd Edition (written by creators)
Eclipse Modeling Framework (EMF)
Discover the Eclipse Modeling Framework (EMF) and Its Dynamic Capabilities
Creating Dynamic EMF Models From XSDs and Loading its Instances From XML as SDOs

This is a fairly complete sample on how to parse an XSD using XSOM:
import java.io.File;
import java.util.Iterator;
import java.util.Vector;
import org.xml.sax.ErrorHandler;
import com.sun.xml.xsom.XSComplexType;
import com.sun.xml.xsom.XSElementDecl;
import com.sun.xml.xsom.XSFacet;
import com.sun.xml.xsom.XSModelGroup;
import com.sun.xml.xsom.XSModelGroupDecl;
import com.sun.xml.xsom.XSParticle;
import com.sun.xml.xsom.XSRestrictionSimpleType;
import com.sun.xml.xsom.XSSchema;
import com.sun.xml.xsom.XSSchemaSet;
import com.sun.xml.xsom.XSSimpleType;
import com.sun.xml.xsom.XSTerm;
import com.sun.xml.xsom.impl.Const;
import com.sun.xml.xsom.parser.XSOMParser;
import com.sun.xml.xsom.util.DomAnnotationParserFactory;
public class XSOMNavigator
{
public static class SimpleTypeRestriction
{
public String[] enumeration = null;
public String maxValue = null;
public String minValue = null;
public String length = null;
public String maxLength = null;
public String minLength = null;
public String[] pattern = null;
public String totalDigits = null;
public String fractionDigits = null;
public String whiteSpace = null;
public String toString()
{
String enumValues = "";
if (enumeration != null)
{
for(String val : enumeration)
{
enumValues += val + ", ";
}
enumValues = enumValues.substring(0, enumValues.lastIndexOf(','));
}
String patternValues = "";
if (pattern != null)
{
for(String val : pattern)
{
patternValues += "(" + val + ")|";
}
patternValues = patternValues.substring(0, patternValues.lastIndexOf('|'));
}
String retval = "";
retval += minValue == null ? "" : "[MinValue = " + minValue + "]\t";
retval += maxValue == null ? "" : "[MaxValue = " + maxValue + "]\t";
retval += minLength == null ? "" : "[MinLength = " + minLength + "]\t";
retval += maxLength == null ? "" : "[MaxLength = " + maxLength + "]\t";
retval += pattern == null ? "" : "[Pattern(s) = " + patternValues + "]\t";
retval += totalDigits == null ? "" : "[TotalDigits = " + totalDigits + "]\t";
retval += fractionDigits == null ? "" : "[FractionDigits = " + fractionDigits + "]\t";
retval += whiteSpace == null ? "" : "[WhiteSpace = " + whiteSpace + "]\t";
retval += length == null ? "" : "[Length = " + length + "]\t";
retval += enumeration == null ? "" : "[Enumeration Values = " + enumValues + "]\t";
return retval;
}
}
private static void initRestrictions(XSSimpleType xsSimpleType, SimpleTypeRestriction simpleTypeRestriction)
{
XSRestrictionSimpleType restriction = xsSimpleType.asRestriction();
if (restriction != null)
{
Vector<String> enumeration = new Vector<String>();
Vector<String> pattern = new Vector<String>();
for (XSFacet facet : restriction.getDeclaredFacets())
{
if (facet.getName().equals(XSFacet.FACET_ENUMERATION))
{
enumeration.add(facet.getValue().value);
}
if (facet.getName().equals(XSFacet.FACET_MAXINCLUSIVE))
{
simpleTypeRestriction.maxValue = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_MININCLUSIVE))
{
simpleTypeRestriction.minValue = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_MAXEXCLUSIVE))
{
simpleTypeRestriction.maxValue = String.valueOf(Integer.parseInt(facet.getValue().value) - 1);
}
if (facet.getName().equals(XSFacet.FACET_MINEXCLUSIVE))
{
simpleTypeRestriction.minValue = String.valueOf(Integer.parseInt(facet.getValue().value) + 1);
}
if (facet.getName().equals(XSFacet.FACET_LENGTH))
{
simpleTypeRestriction.length = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_MAXLENGTH))
{
simpleTypeRestriction.maxLength = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_MINLENGTH))
{
simpleTypeRestriction.minLength = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_PATTERN))
{
pattern.add(facet.getValue().value);
}
if (facet.getName().equals(XSFacet.FACET_TOTALDIGITS))
{
simpleTypeRestriction.totalDigits = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_FRACTIONDIGITS))
{
simpleTypeRestriction.fractionDigits = facet.getValue().value;
}
if (facet.getName().equals(XSFacet.FACET_WHITESPACE))
{
simpleTypeRestriction.whiteSpace = facet.getValue().value;
}
}
if (enumeration.size() > 0)
{
simpleTypeRestriction.enumeration = enumeration.toArray(new String[] {});
}
if (pattern.size() > 0)
{
simpleTypeRestriction.pattern = pattern.toArray(new String[] {});
}
}
}
private static void printParticle(XSParticle particle, String occurs, String absPath, String indent)
{
boolean repeats = particle.isRepeated();
occurs = " MinOccurs = " + particle.getMinOccurs() + ", MaxOccurs = " + particle.getMaxOccurs() + ", Repeats = " + Boolean.toString(repeats);
XSTerm term = particle.getTerm();
if (term.isModelGroup())
{
printGroup(term.asModelGroup(), occurs, absPath, indent);
}
else if(term.isModelGroupDecl())
{
printGroupDecl(term.asModelGroupDecl(), occurs, absPath, indent);
}
else if (term.isElementDecl())
{
printElement(term.asElementDecl(), occurs, absPath, indent);
}
}
private static void printGroup(XSModelGroup modelGroup, String occurs, String absPath, String indent)
{
System.out.println(indent + "[Start of Group " + modelGroup.getCompositor() + occurs + "]" );
for (XSParticle particle : modelGroup.getChildren())
{
printParticle(particle, occurs, absPath, indent + "\t");
}
System.out.println(indent + "[End of Group " + modelGroup.getCompositor() + "]");
}
private static void printGroupDecl(XSModelGroupDecl modelGroupDecl, String occurs, String absPath, String indent)
{
System.out.println(indent + "[GroupDecl " + modelGroupDecl.getName() + occurs + "]");
printGroup(modelGroupDecl.getModelGroup(), occurs, absPath, indent);
}
private static void printComplexType(XSComplexType complexType, String occurs, String absPath, String indent)
{
System.out.println();
XSParticle particle = complexType.getContentType().asParticle();
if (particle != null)
{
printParticle(particle, occurs, absPath, indent);
}
}
private static void printSimpleType(XSSimpleType simpleType, String occurs, String absPath, String indent)
{
SimpleTypeRestriction restriction = new SimpleTypeRestriction();
initRestrictions(simpleType, restriction);
System.out.println(restriction.toString());
}
public static void printElement(XSElementDecl element, String occurs, String absPath, String indent)
{
absPath += "/" + element.getName();
String typeName = element.getType().getBaseType().getName();
if(element.getType().isSimpleType() && element.getType().asSimpleType().isPrimitive())
{
// We have a primitive type - So use that instead
typeName = element.getType().asSimpleType().getPrimitiveType().getName();
}
boolean nillable = element.isNillable();
System.out.print(indent + "[Element " + absPath + " " + occurs + "] of type [" + typeName + "]" + (nillable ? " [nillable] " : ""));
if (element.getType().isComplexType())
{
printComplexType(element.getType().asComplexType(), occurs, absPath, indent);
}
else
{
printSimpleType(element.getType().asSimpleType(), occurs, absPath, indent);
}
}
public static void printNameSpace(XSSchema s, String indent)
{
String nameSpace = s.getTargetNamespace();
// We do not want the default XSD namespaces or a namespace with nothing in it
if(nameSpace == null || Const.schemaNamespace.equals(nameSpace) || s.getElementDecls().isEmpty())
{
return;
}
System.out.println("Target namespace: " + nameSpace);
Iterator<XSElementDecl> jtr = s.iterateElementDecls();
while (jtr.hasNext())
{
XSElementDecl e = (XSElementDecl) jtr.next();
String occurs = "";
String absPath = "";
XSOMNavigator.printElement(e, occurs, absPath,indent);
System.out.println();
}
}
public static void xsomNavigate(File xsdFile)
{
ErrorHandler errorHandler = new ErrorReporter(System.err);
XSSchemaSet schemaSet = null;
XSOMParser parser = new XSOMParser();
try
{
parser.setErrorHandler(errorHandler);
parser.setAnnotationParser(new DomAnnotationParserFactory());
parser.parse(xsdFile);
schemaSet = parser.getResult();
}
catch (Exception exp)
{
exp.printStackTrace(System.out);
}
if(schemaSet != null)
{
// iterate each XSSchema object. XSSchema is a per-namespace schema.
Iterator<XSSchema> itr = schemaSet.iterateSchema();
while (itr.hasNext())
{
XSSchema s = (XSSchema) itr.next();
String indent = "";
printNameSpace(s, indent);
}
}
}
public static void printFile(String fileName)
{
File fileToParse = new File(fileName);
if (fileToParse != null && fileToParse.canRead())
{
xsomNavigate(fileToParse);
}
}
}
And for your Error Reporter use:
import java.io.OutputStream;
import java.io.PrintStream;
import java.text.MessageFormat;
import org.xml.sax.ErrorHandler;
import org.xml.sax.SAXException;
import org.xml.sax.SAXParseException;
public class ErrorReporter implements ErrorHandler {
private final PrintStream out;
public ErrorReporter( PrintStream o ) { this.out = o; }
public ErrorReporter( OutputStream o ) { this(new PrintStream(o)); }
public void warning(SAXParseException e) throws SAXException {
print("[Warning]",e);
}
public void error(SAXParseException e) throws SAXException {
print("[Error ]",e);
}
public void fatalError(SAXParseException e) throws SAXException {
print("[Fatal ]",e);
}
private void print( String header, SAXParseException e ) {
out.println(header+' '+e.getMessage());
out.println(MessageFormat.format(" line {0} at {1}",
new Object[]{
Integer.toString(e.getLineNumber()),
e.getSystemId()}));
}
}
For your main use:
public class WDXSOMParser
{
public static void main(String[] args)
{
String fileName = null;
if(args != null && args.length > 0 && args[0] != null)
fileName = args[0];
else
fileName = "C:\\xml\\CollectionComments\\CollectionComment1.07.xsd";
//fileName = "C:\\xml\\PropertyListingContractSaleInfo\\PropertyListingContractSaleInfo.xsd";
//fileName = "C:\\xml\\PropertyPreservation\\PropertyPreservation.xsd";
XSOMNavigator.printFile(fileName);
}
}

It's agood bit of work depending on how compex your xsd is but basically.
if you had
<Document>
<Header/>
<Body/>
<Document>
And you wanted to find out where were the alowable children of header you'd (taking account of namespaces)
Xpath would have you look for '/element[name="Document"]/element[name="Header"]'
After that it depends on how much you want to do. You might find it easier to write or find something that loads an xsd into a DOM type structure.
Course you are going to possibly find all sorts of things under that elment in xsd, choice, sequence, any, attributes, complexType, SimpleContent, annotation.
Loads of time consuming fun.

Have a look at this.
How to parse schema using XOM Parser.
Also, here is the project home for XOM