SAX Parser - How To Handle Bad Data From .XML File - java

I need to make a program that takes an .xml file that uses the SAX Parser in Java to parse the .xml file, store it in an arrayList and then call methods to display certain objects with the arrayList.
My program needs to be able to handle the user giving the SAX Parser bad data such that if it doesn’t have a certain tag it’s looking for, then it won’t break. I need it to be able to load the data and use a “check” command to check the intergrity of the data. For example, if the customer doest’t have an account associated with it, the program will output which customer doesn’t have an account.
Below, I’ve put the task for the program, the Handler, and the .xml with bad data below.
Task for the program:
check : This command is used to check the integrity of the named entries. In other words, it checks to see that all the entries of a given type are correct. For example, if the command is:
check customer
the program should list all customers (first name and last name) that do not have any accounts. Related commands include:
check account : list any account number without an associated address
check address : list any address without an associated meter
check meter : list any meter id without any meter readings, or whose readings do not match the meter type, e.g., push reading from a polling meter.
.xml File:
<xml version="1.0" encoding="UTF-8">
<!-- Customer with no account -->
<customer lastName ="Anderson" firstName="Thomas">
</customer>
<!-- Account with no address -->
<customer lastName ="Baker" firstName="Susanne">
<account type="residential" accountNumber="999-999-99">
</account>
</customer>
<!-- Address with no meter -->
<customer lastName ="Charles" firstName="Henry">
<account type="residential" accountNumber="888-888-88">
<address type="apartment" unit="308" street="E 6th St." number="56" zipCode="13126"/>
</account>
</customer>
<!-- Meter with no readings -->
<customer lastName ="Davidson" firstName="Mary">
<account type="residential" accountNumber="666-666-66">
<address type="apartment" unit="308" street="W 9th St." number="67" zipCode="13126">
<meter id = "RM-4876-X4" brand="GE" type="poll" location = "West side of building"/>
</address>
</account>
</customer>
<!-- Meter with mismatched readings -->
<customer lastName ="Evans" firstName="Oscar">
<account type="residential" accountNumber="555-555-55">
<address type="house" street="E 10th St." number="78" zipCode="13126">
<meter id = "RM-4874-X4" brand="GE" type="poll" location = "North side">
<meterReading reading="650" date = "1413227815" flag="poll"/>
<meterReading reading="675" date = "1413314215" flag="push"/>
<meterReading reading="622" date = "1413400615" flag="poll"/>
</meter>
</address>
</account>
</customer>
</xml>
Handler File:
package csc241hw07;
import java.time.LocalDateTime;
import java.time.ZoneId;
import java.time.ZoneOffset;
import java.util.ArrayList;
import java.util.List;
import org.xml.sax.Attributes;
import org.xml.sax.SAXException;
import org.xml.sax.helpers.DefaultHandler;
public class MyHandler extends DefaultHandler {
// Variables to hold current values
private ArrayList<Customer> customerList = new ArrayList<Customer>();
private Customer currentCustomer;
private Account currentAccount;
private Address currentAddress;
private Meter currentMeter;
//getter method for employee list
public ArrayList<Customer> getCustList() {
return customerList;
}
#Override
public void startElement(String uri, String localName, String qName, Attributes attributes)
throws SAXException {
if (qName.equalsIgnoreCase("customer")) {
//Create a customer object
String lastName = attributes.getValue("lastName");
String firstName = attributes.getValue("firstName");
currentCustomer = new Customer(lastName, firstName);
} else if (qName.equalsIgnoreCase("address")) {
// Create an Address object
String street = attributes.getValue("street");
int houseNumber = Integer.parseInt(attributes.getValue("number"));
String zipCode = attributes.getValue("zipCode");
String type = attributes.getValue("type");
String unit = attributes.getValue("unit");
if (type.equalsIgnoreCase("mailing")) {
// this is a mailing address -- assign to current customer
MailingAddress ma = new MailingAddress(street, houseNumber, zipCode, type);
currentCustomer.setMailingAddress(ma);
} else if (type.equalsIgnoreCase("house")) {
// Create a house
currentAddress = new House(street, houseNumber, zipCode, type);
} else if (type.equalsIgnoreCase("commercial")) {
// Create a commercial
currentAddress = new Commercial(street, houseNumber, zipCode, type);
} else if (unit != null) {
// Create an apartment
currentAddress = new Apartment(street, houseNumber, zipCode, type, unit);
} else {
System.out.println("Unknown address type:" + type);
}
if (currentAddress != null) {
// Assign this account to current address
currentAddress.setAccount(currentAccount);
currentAccount.addAddress(currentAddress);
}
} else if (qName.equalsIgnoreCase("meter")) {
// Create a meter object
String type = attributes.getValue("type");
String brand = attributes.getValue("brand");
String id = attributes.getValue("id");
if (type.equalsIgnoreCase("push")) {
currentMeter = new PushMeter(id, brand, type);
} else if (type.equalsIgnoreCase("poll")) {
currentMeter = new PollMeter(id, brand, type);
} else {
System.out.println("Unknown meter type: " + type);
}
if (currentMeter != null) {
// Set location
String location = attributes.getValue("location");
currentMeter.setLocation(currentAddress, location);
currentAddress.addMeter(currentMeter);
}
//System.out.println("METER:");
} else if (qName.equalsIgnoreCase("meterReading")) {
// Create a meter reading
//<meterReading reading="622" date = "1413400615" flag="push"/>
double reading = Double.parseDouble(attributes.getValue("reading"));
//System.out.println("DATE:" );
ZoneOffset z = ZoneOffset.ofHours(5);
long epoch = Long.parseLong(attributes.getValue("date"));
LocalDateTime d = LocalDateTime.ofEpochSecond(epoch,0,z);
//System.out.println("DATE:" + d.toString());
String flag = attributes.getValue("flag");
MeterReading mr = new MeterReading(reading, d, flag, currentMeter);
// Add this to current meter
currentMeter.addReading(mr);
//System.out.println("METERREADING:");
} else if (qName.equalsIgnoreCase("account")) {
// <account type="residential" accountNumber="876-543-21">
String type = attributes.getValue("type");
String acctNum = attributes.getValue("accountNumber");
if (type.equalsIgnoreCase("residential")) {
// residential account
currentAccount = new ResidentialAccount(acctNum, currentCustomer);
} else if (type.equalsIgnoreCase("commercial")) {
currentAccount = new CommercialAccount(acctNum, currentCustomer);
} else {
System.out.println("Unknown account type:" + type);
}
if (currentAccount != null) {
// Add this account to current customer
currentCustomer.addAccount(currentAccount);
}
}
}
#Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (qName.equalsIgnoreCase("customer")) {
customerList.add(currentCustomer);
currentCustomer = null;
} else if (qName.equalsIgnoreCase("meter")) {
currentMeter = null;
} else if (qName.equalsIgnoreCase("account")) {
currentAccount = null;
} else if (qName.equalsIgnoreCase("address")) {
currentAddress = null;
}
}
}
Thank you!

You can add one more list with "bad" customers like:
// Variables to hold current values
private ArrayList<Customer> customerList = new ArrayList<Customer>();
private ArrayList<Customer> badCustomerList = new ArrayList<Customer>();
...
And add some changes sorting those customers out of "good" ones. For instance:
#Override
public void endElement(String uri, String localName, String qName) throws SAXException {
if (qName.equalsIgnoreCase("customer")) {
if (isCustomerGood(currentCustomer)) { // Here is checking code
customerList.add(currentCustomer);
} else {
badCustomerList.add(currentCustomer);
}
currentCustomer = null;
} else if (qName.equalsIgnoreCase("meter")) {
currentMeter = null;
} else if (qName.equalsIgnoreCase("account")) {
currentAccount = null;
} else if (qName.equalsIgnoreCase("address")) {
currentAddress = null;
}
}
private static boolean isCustomerGood(Customer customer) {
return customer.getAccount() != null;
}
public boolean check() {
return badCustomerList.isEmpty();
}
public List<Customer> getBadCustomers() {
return badCustomerList;
}
Actually you can implement isCustomerGood differently depending on your needs. Now you just run check method at the end of parsing.

First of all, by bad data I dont think you mean a non-wellformed XML file that causes parsing exception.
If the above assumption is true, then I think you should consider using XPath to query the data file and check for the condition where the target element does not exist...
So why are you not using XPath which would make your code a lot easier to write and maintain?

Related

How to print out a list item based on its status?

I'm creating an eAuction system and I have a method for browsing auctions. Each auction has a status (OPEN or CLOSED) and I want the browseAuctions method to only print out auctions that are opened.
I've tried a number of if statements and it always keeps printing out every single auction.
The following code is a few things I've hardcoded to test the system
public List<Auction> auctionSystem() throws Exception {
List<Auction> auctions = new LinkedList<Auction>();
auctions.add(new Auction (35.50, 75.50, 40.00, users.get(3), LocalDateTime.now().minusSeconds(60), "Xbox", users.get(1), Status.OPEN));
auctions.add(new Auction (27.00, 42.00, 32.00, users.get(2), LocalDateTime.now().plusSeconds(10), "PS3", users.get(1), Status.OPEN));
auctions.add(new Auction (19.00, 21.00, 50.00, users.get(2), LocalDateTime.now().minusSeconds(1), "iPhone", users.get(1), Status.CLOSED));
return auctions;
}
This is the Auction class constructor:
public Auction (double startPrice, double reservePrice, double currentBid, User highestBidder, LocalDateTime closeDate, String item, User seller, Status status) throws Exception {
if (closeDate.isBefore(LocalDateTime.now().plusDays(7))) {
this.startPrice = startPrice;
this.reservePrice = reservePrice;
this.closeDate = closeDate;
this.item = item;
this.highestBidder = highestBidder;
this.currentBid = currentBid;
this.seller = seller;
UP = currentBid * 0.20;
LOW = currentBid * 0.10;
} else {
throw new Exception ("CloseDate error: " + closeDate.format(formatter));
}
}
This is the Status class:
public enum Status {
OPEN, CLOSED
}
This is the method inside the Auction class to browse auctions:
public void browseAuctions () {
System.out.println("-----All Auctions-----");
for (Auction a : auctions) {
if (a.status.equals(Status.OPEN)){
System.out.println("Item: " + a.getItem());
System.out.println("Current Bid: " + "£" + a.getCurrentBid());
System.out.println("Close Date: " + a.getCloseDate());
}
}
}
}
The status is ignored in the constructor, therefore all the Auction instances shall be not be qualified according to the condition in the loop. I wonder all pass and the only explanation is that the Status.OPEN is set by default, it means you have the following declaration in the code:
private Status status = Status.OPEN;
Since it is missing in the constructor, it is not set to a new passed value. These are problems with mutable fields, so I suggest you declare them final and resolve a default value with a secondary constructor:
private final Status status;
// the rest
public Auction (double sPrice, double rPrice, double currentBid,
User highestBidder, LocalDateTime closeDate, String item, User seller)
{
this(sPrice, rPrice, currentBid, highestBidder, closeDate, item, seller, Status.OPEN)
}
Anyway, to fix your issue, complete the constructor with:
this.status = status;

How to Solve Deserialization error ask sdk

I'm attempting to convert the JSON output from my session and map it to a class that I've created using JAVA's ObjectMapper. When I run my tests on Lambda I get a Deserialisation error:
Deserialization error: com.amazon.ask.exception.AskSdkException
com.amazon.ask.exception.AskSdkException: Deserialization error
at com.amazon.ask.util.impl.JacksonJsonUnmarshaller.unmarshall(JacksonJsonUnmarshaller.java:50)
at com.amazon.ask.impl.AbstractSkill.execute(AbstractSkill.java:44)
at com.amazon.ask.AlexaSkill.execute(AlexaSkill.java:22)
at com.amazon.ask.SkillStreamHandler.handleRequest(SkillStreamHandler.java:71)
Caused by: com.fasterxml.jackson.databind.exc.InvalidTypeIdException: Could not resolve type id 'AnswerIntent' as a subtype of [simple type, class com.amazon.ask.model.Request]: known type ids = [Alexa.Presentation.APL.UserEvent, AlexaHouseholdListEvent.ItemsCreated, AlexaHouseholdListEvent.ItemsDeleted, AlexaHouseholdListEvent.ItemsUpdated, AlexaHouseholdListEvent.ListCreated, AlexaHouseholdListEvent.ListDeleted, AlexaHouseholdListEvent.ListUpdated, AlexaSkillEvent.SkillAccountLinked, AlexaSkillEvent.SkillDisabled, AlexaSkillEvent.SkillEnabled, AlexaSkillEvent.SkillPermissionAccepted, AlexaSkillEvent.SkillPermissionChanged, AudioPlayer.PlaybackFailed, AudioPlayer.PlaybackFinished, AudioPlayer.PlaybackNearlyFinished, AudioPlayer.PlaybackStarted, AudioPlayer.PlaybackStopped, Connections.Request, Connections.Response, Display.ElementSelected, GameEngine.InputHandlerEvent, IntentRequest, LaunchRequest, Messaging.MessageReceived, PlaybackController.NextCommandIssued, PlaybackController.PauseCommandIssued, PlaybackController.PlayCommandIssued, PlaybackController.PreviousCommandIssued, SessionEndedRequest, System.ExceptionEncountered] (for POJO property 'request')
at [Source: UNKNOWN; line: -1, column: -1] (through reference chain: com.amazon.ask.model.RequestEnvelope$Builder["request"])
at com.fasterxml.jackson.databind.exc.InvalidTypeIdException.from(InvalidTypeIdException.java:43)
at com.fasterxml.jackson.databind.DeserializationContext.invalidTypeIdException(DeserializationContext.java:1628)
at com.fasterxml.jackson.databind.DeserializationContext.handleUnknownTypeId(DeserializationContext.java:1186)
at com.fasterxml.jackson.databind.jsontype.impl.TypeDeserializerBase._handleUnknownTypeId(TypeDeserializerBase.java:291)
at com.fasterxml.jackson.databind.jsontype.impl.TypeDeserializerBase._findDeserializer(TypeDeserializerBase.java:162)
at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer._deserializeTypedForId(AsPropertyTypeDeserializer.java:113)
at com.fasterxml.jackson.databind.jsontype.impl.AsPropertyTypeDeserializer.deserializeTypedFromObject(AsPropertyTypeDeserializer.java:97)
at com.fasterxml.jackson.databind.deser.AbstractDeserializer.deserializeWithType(AbstractDeserializer.java:254)
at com.fasterxml.jackson.databind.deser.impl.MethodProperty.deserializeSetAndReturn(MethodProperty.java:151)
at com.fasterxml.jackson.databind.deser.BuilderBasedDeserializer.vanillaDeserialize(BuilderBasedDeserializer.java:269)
at com.fasterxml.jackson.databind.deser.BuilderBasedDeserializer.deserialize(BuilderBasedDeserializer.java:193)
at com.fasterxml.jackson.databind.ObjectMapper._readValue(ObjectMapper.java:3972)
at com.fasterxml.jackson.databind.ObjectMapper.readValue(ObjectMapper.java:2264)
at com.fasterxml.jackson.databind.ObjectMapper.treeToValue(ObjectMapper.java:2746)
at com.amazon.ask.util.impl.JacksonJsonUnmarshaller.unmarshall(JacksonJsonUnmarshaller.java:48)
... 3 more
I did checks to ensure that my "riddleItem" variable is not null. The JSON values are being mapped to the Person class which just returns properties of a person. The code is shown below and I've highlighted the line which the error occurs on:
public Optional<Response> handle(HandlerInput input) {
Map<String, Object> sessionAttributes = input.getAttributesManager().getSessionAttributes();
System.out.println("This a FIRST debug");
LOG.debug("This a FIRST debug");
boolean correctAnswer;
String speechText = null, response;
System.out.println("This a SECOND debug");
Map<String, String> riddleItem = (LinkedHashMap<String, String>)sessionAttributes.get(Attributes.RIDDLE_ITEM_KEY);
Person person;
// System.out.println("riddleItem " + riddleItem);
if(riddleItem != null)
{
person = MAPPER.convertValue(riddleItem, Person.class); // ERROR OCCURS ON THIS LINE
}
System.out.println("This a THIRD debug");
PersonProperty personProperty = PersonProperty.valueOf((String) sessionAttributes.get(Attributes.RIDDLE_PROPERTY_KEY));
int counter = (int) sessionAttributes.get(Attributes.COUNTER_KEY);
int riddleGameScore = (int) sessionAttributes.get(Attributes.RIDDLE_SCORE_KEY);
System.out.println("This a FOURTH debug");
IntentRequest intentRequest = (IntentRequest) input.getRequestEnvelope().getRequest();
correctAnswer = compareSlots(intentRequest.getIntent().getSlots(), getPropertyOfPerson(personProperty, person));
System.out.println("This a FIFTH debug " + correctAnswer);
if(correctAnswer)
{
riddleGameScore++;
response = getSpeechExpressionCon(true);
System.out.println("This a SIXTH debug " + response);
sessionAttributes.put(Attributes.RIDDLE_SCORE_KEY, riddleGameScore);
}
else
{
response = getSpeechExpressionCon(false);
System.out.println("This a SEVENTH debug " + response);
}
AnswerIntentHandler setup = new AnswerIntentHandler();
//
if(riddle.getAnswer() != null)
{
speechText = "Hello " + riddle.getAnswer();
}
return input.getResponseBuilder()
.withSimpleCard("RiddleSession", speechText)
.withSpeech(speechText)
.withShouldEndSession(true)
.build();
}
[Json Output of properties under "riddleItem" during Session]1
I know my the values being mapped aren't empty thus I'm at a complete loss of ideas as to what's going on as I've come up short with possible ideas as to what the problem might be.
I solved the problem as I came to realise that when mapping from JSON to a class, methods ('set' methods) for assigning the JSON values to the variables in the class must be created. A sample structure for example:
public class State {
public State() {}
public State(String name, String abbreviation, String capital, String statehoodYear, String statehoodOrder) {
this.name = name;
this.abbreviation = abbreviation;
this.capital = capital;
this.statehoodYear = statehoodYear;
this.statehoodOrder = statehoodOrder;
}
public String getName() {
return name;
}
public String getAbbreviation() {
return abbreviation;
}
public String getCapital() {
return capital;
}
public String getStatehoodYear() { return statehoodYear; }
public String getStatehoodOrder() {
return statehoodOrder;
}
public void setName(String name) {
this.name = name;
}
public void setAbbreviation(String abbreviation) {
this.abbreviation = abbreviation;
}
public void setCapital(String capital) {
this.capital = capital;
}
public void setStatehoodYear(String statehoodYear) {
this.statehoodYear = statehoodYear;
}
public void setStatehoodOrder(String statehoodOrder) {
this.statehoodOrder = statehoodOrder;
}
}
The declaration of an empty constructor is necessary when making use of multiple constructors where, one is parametric. In some cases without the inclusion of such constructor an error may be thrown so, to avoid the possibility of said error, adding the constructor as a "Dummy" so to say, is essential.

Java Tapestry Autocomplete typeahead include ID on listing

I have a textfield which uses autocomplete mixin on tapestry. The mixin is working fine as it is, but I am having a problem with tagging the values of list of names with duplicate values. Now I am wondering if I can somehow pass the id of the data on autocomplete upon selection.
Here is my code for pupulating the list.
List<String> onProvideCompletionsFromUserName(String partial) {
List<String> matches = new ArrayList<String>();
String partialUpper = partial.toUpperCase();
List<User> users = clientFinder.findUsers();
// int i = 0;
for (User user : users){
String name = NameUtil.toName(user.getFirstName(), user.getFamilyName());
if (name.toUpperCase().contains(partialUpper)) {
matches.add(name );
// if (i++ >= 5) {
// break;
// }
}
}
return matches;
}
Is there a way for me to pass the ID with the list like
(List onProvideCompletionsFromUserName)?
Has anyone encountered this problem as well ? Thanks for your response.
The only way I was able to do it was by extending the Autocomplete mixin with my own version, as the configure method in the mixin is marked protected. Here is my class. Note that I am firing my own event. You will have to give your own values for label, value and uid in the providecompletions handler. The zone parameter is the zone you want to update when the user clicks and item in the completion list.
Mixin:
import java.util.ArrayList;
import java.util.List;
import org.apache.tapestry5.BindingConstants;
import org.apache.tapestry5.ComponentResources;
import org.apache.tapestry5.annotations.OnEvent;
import org.apache.tapestry5.annotations.Parameter;
import org.apache.tapestry5.ioc.annotations.Inject;
import org.apache.tapestry5.json.JSONLiteral;
import org.apache.tapestry5.json.JSONObject;
import org.got5.tapestry5.jquery.mixins.Autocomplete;
public class UserAutocomplete extends Autocomplete {
public static final String CHANGE_EVENT_NAME = "autocompleteUser";
#Inject
private ComponentResources resources;
#Parameter(defaultPrefix=BindingConstants.LITERAL)
private String zone;
#OnEvent(value = "provideCompletions")
public List<JSONObject> autoComplete(String query) {
List<JSONObject> strings = new ArrayList<JSONObject>();
if(query != null) {
for(User u : service.searchUsers(query.trim())) {
JSONObject so = new JSONObject();
String name = u.getName();
so.put("label", name);
so.put("value", name);
so.put("uid", u.getId());
strings.add(so);
}
}
return strings;
}
protected void configure(JSONObject config) {
config.put("url", resources.createEventLink("autocomplete").toURI());
String url = resources.createEventLink(CHANGE_EVENT_NAME).toURI();
config.put("options", new JSONObject().put("select", new JSONLiteral("function(e, d) {var zone = $('#" + zone + "'); if (!zone) { return; } "
+ "zone.tapestryZone('update', {url: '" + url + "'+'/'+d.item.uid});}")));
}
}
Page Template:
<t:textfield value="query" autocomplete="off" t:mixins="UserAutocomplete" t:zone="resultZone" />
Page Class:
...
#InjectComponent
private Zone resultZone;
#OnEvent(value = UserAutocomplete.CHANGE_EVENT_NAME)
void userChange(Integer id) {
User selectedUser = service.findUser(id);
renderer.addRender(resultZone);
}

balana custom AttributeFinderModule never called

After checking out the k-market sample from balana (http://svn.wso2.org/repos/wso2/trunk/commons/balana/modules/balana-samples/kmarket-trading-sample/) i wanted to create a similar sample project. I have created the following 2 classes. The balana source was downloaded from the same trunk.
public class Test {
public static void main(String[] args) throws JDOMException, IOException, SAXException, URISyntaxException {
//Create the xacml request as a string
Document xacmlRequest = createXACMLRequest();
String requestString = writeRequestToString(xacmlRequest);
//Specify XACML Policies Directory
//System.setProperty(ConfigurationStore.PDP_CONFIG_PROPERTY, "Config/config.xml");
System.setProperty(FileBasedPolicyFinderModule.POLICY_DIR_PROPERTY, "Policies");
Balana balana = Balana.getInstance();
PDPConfig pdpConfig = balana.getPdpConfig();
//Keep ONLY my SampleAttributeFinderModule for testing purposes
AttributeFinder attributeFinder = pdpConfig.getAttributeFinder();
//List<AttributeFinderModule> modules = attributeFinder.getModules();
List<AttributeFinderModule> modules = new ArrayList<AttributeFinderModule>();
modules.add(new SampleAttributeFinderModule());
attributeFinder.setModules(modules);
PDPConfig newPDPConfig = new PDPConfig(attributeFinder, pdpConfig.getPolicyFinder(), pdpConfig.getResourceFinder(), false);
PDP pdp = new PDP(newPDPConfig);
System.out.println(pdp.evaluate(requestString));
}
and
public class SampleAttributeFinderModule extends AttributeFinderModule {
#Override
public boolean isDesignatorSupported() {
return true;
}
#Override
public Set<String> getSupportedCategories() {
Set<String> categories = new HashSet<String>();
categories.add("urn:oasis:names:tc:xacml:3.0:attribute-category:resource");
return categories;
}
#Override
public Set getSupportedIds() {
Set<String> ids = new HashSet<String>();
ids.add("http://wso2.org/claims/emailaddress");
return ids;
}
#Override
public EvaluationResult findAttribute(URI attributeType, URI attributeId, String issuer,
URI category, EvaluationCtx context) {
System.out.println("Custom Attribute Finder initiated");
List<AttributeValue> attributeValues = new ArrayList<AttributeValue>();
//Just return the same value, for test purposes
attributeValues.add(new StringAttribute("Tom"));
return new EvaluationResult(new BagAttribute(attributeType, attributeValues));
}
While i think the above code should work , my SampleAttributeFinderModule is never called, and the evaluation only succeeds if my request contains the specified attribute. My Policy is this :
<Policy xmlns="urn:oasis:names:tc:xacml:3.0:core:schema:wd-17"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="urn:oasis:names:tc:xacml:3.0:core:schema:wd-17 http://docs.oasis-open.org/xacml/3.0/xacml-core-v3-schema-wd-17.xsd"
Version="1.0"
PolicyId="SamplePolicy"
RuleCombiningAlgId="urn:oasis:names:tc:xacml:1.0:rule-combining-algorithm:permit-overrides">
<Target/>
<!-- Rule to see if we should allow the Subject to login -->
<Rule RuleId="LoginRule" Effect="Permit">
<Target/>
<Condition>
<Apply FunctionId="urn:oasis:names:tc:xacml:1.0:function:string-equal">
<Apply FunctionId="urn:oasis:names:tc:xacml:1.0:function:string-one-and-only">
<AttributeDesignator
AttributeId="urn:oasis:names:tc:xacml:1.0:subject:subject-id"
Category="urn:oasis:names:tc:xacml:1.0:subject-category:access-subject"
DataType="http://www.w3.org/2001/XMLSchema#string"
MustBePresent="true"/>
</Apply>
<Apply FunctionId="urn:oasis:names:tc:xacml:1.0:function:string-one-and-only">
<AttributeDesignator
AttributeId="http://wso2.org/claims/emailaddress"
Category="urn:oasis:names:tc:xacml:1.0:subject-category:resource"
DataType="http://www.w3.org/2001/XMLSchema#string"
MustBePresent="true"/>
</Apply>
</Apply>
</Condition>
</Rule>
<!-- We could include other Rules for different actions here -->
<!-- A final, "fall-through" Rule that always Denies -->
<Rule RuleId="FinalRule" Effect="Deny"/>
</Policy>
Any help would be appreciated. Note that, after looking at the balana source , and after tracking how it's methods are called, i stumbled upon the following piece of code (im sure this is called when i run the program). It seems like it first tries to get the attributes from the request, but the first if always evaluates to false if the attributeis not in the request (i think), so the callHelper method which contains the modules is never called. Is this intended?
package org.wso2.balana.ctx.xacml3;
public class XACML3EvaluationCtx extends BasicEvaluationCtx {
// other methods
public EvaluationResult getAttribute(URI type, URI id, String issuer, URI category) {
List<AttributeValue> attributeValues = new ArrayList<AttributeValue>();
Set<Attributes> attributesSet = mapAttributes.get(category.toString());
if(attributesSet != null && attributesSet.size() > 0){
Set<Attribute> attributeSet = attributesSet.iterator().next().getAttributes();
for(Attribute attribute : attributeSet) {
if(attribute.getId().equals(id) && attribute.getType().equals(type)
&& (issuer == null || issuer.equals(attribute.getIssuer()))
&& attribute.getValue() != null){
List<AttributeValue> attributeValueList = attribute.getValues();
for (AttributeValue attributeVal : attributeValueList) {
attributeValues.add(attributeVal);
}
}
}
if(attributeValues.size() < 1){
return callHelper(type, id, issuer, category);
}
}
//If i put this piece of code here instead of up there (outside the first if) , it works as i want to
/*if(attributeValues.size() < 1){
return callHelper(type, id, issuer, category);
}*/
// if we got here, then we found at least one useful AttributeValue
return new EvaluationResult(new BagAttribute(type, attributeValues));
}

Can I use MyBatis to generate Dynamic SQL without executing it?

I have some complex queries to build with a number of optional filters, for which MyBatis seems like an ideal candidate for generating dynamic SQL.
However, I still want my query to execute in the same framework as the rest of the application (which is not using MyBatis).
So what I was hoping to do was use MyBatis strictly for generating the SQL, but from there using the rest of my app to actually execute it. Is this possible? If so, how?
Although MyBatis was designed to execute the query after it builds it, you can make use of it's configuration and a little bit of "inside knowledge" to get to what you need.
MyBatis is a very nice framework, unfortunately it lacks on the documentations side so the source code is you friend. If you dig around you should bump into these classes: org.apache.ibatis.mapping.MappedStatement and org.apache.ibatis.mapping.BoundSql which are key players into building the dynamic SQL. Here is a basic usage example:
MySQL table user with this data in it:
name login
----- -----
Andy a
Barry b
Cris c
User class:
package pack.test;
public class User {
private String name;
private String login;
// getters and setters ommited
}
UserService interface:
package pack.test;
public interface UserService {
// using a different sort of parameter to show some dynamic SQL
public User getUser(int loginNumber);
}
UserService.xml mapper file:
<mapper namespace="pack.test.UserService">
<select id="getUser" resultType="pack.test.User" parameterType="int">
<!-- dynamic change of parameter from int index to login string -->
select * from user where login = <choose>
<when test="_parameter == 1">'a'</when>
<when test="_parameter == 2">'b'</when>
<otherwise>'c'</otherwise>
</choose>
</select>
</mapper>
sqlmap-config.file:
<configuration>
<settings>
<setting name="lazyLoadingEnabled" value="false" />
</settings>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost/test"/>
<property name="username" value="..."/>
<property name="password" value="..."/>
</dataSource>
</environment>
</environments>
<mappers>
<mapper resource="pack/test/UserService.xml"/>
</mappers>
</configuration>
AppTester to show the result:
package pack.test;
import java.io.Reader;
import org.apache.ibatis.io.Resources;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;
public class AppTester {
private static String CONFIGURATION_FILE = "sqlmap-config.xml";
public static void main(String[] args) throws Exception {
Reader reader = null;
SqlSession session = null;
try {
reader = Resources.getResourceAsReader(CONFIGURATION_FILE);
session = new SqlSessionFactoryBuilder().build(reader).openSession();
UserService userService = session.getMapper(UserService.class);
// three users retreived from index
for (int i = 1; i <= 3; i++) {
User user = userService.getUser(i);
System.out.println("Retreived user: " + user.getName() + " " + user.getLogin());
// must mimic the internal statement key for the mapper and method you are calling
MappedStatement ms = session.getConfiguration().getMappedStatement(UserService.class.getName() + ".getUser");
BoundSql boundSql = ms.getBoundSql(i); // parameter for the SQL statement
System.out.println("SQL used: " + boundSql.getSql());
System.out.println();
}
} finally {
if (reader != null) {
reader.close();
}
if (session != null) {
session.close();
}
}
}
}
And the result:
Retreived user: Andy a
SQL used: select * from user where login = 'a'
Retreived user: Barry b
SQL used: select * from user where login = 'b'
Retreived user: Cris c
SQL used: select * from user where login = 'c'
Everyone knows how to use BoundSql.getSql() to get a paramaterized query string from MyBatis, like this:
// get parameterized query
MappedStatement ms = configuration.getMappedStatement("MyMappedStatementId");
BoundSql boundSql = ms.getBoundSql(parameters);
System.out.println("SQL" + boundSql.getSql());
// SELECT species FROM animal WHERE name IN (?, ?) or id = ?
But now you need the other half of the equation, the list of values that correspond to the question marks:
// get parameters
List<ParameterMapping> boundParams = boundSql.getParameterMappings();
String paramString = "";
for(ParameterMapping param : boundParams) {
paramString += boundSql.getAdditionalParameter(param.getProperty()) + ";";
}
System.out.println("params:" + paramString);
// "Spot;Fluffy;42;"
Now you can serialize it to send elsewhere to be run, or you can print it to a log so you can stitch them together and run the query manually.
*code not tested, might be minor type issues or the like
mybatis version is 3.4.5
Util Class
To convert mapper to sql, need mapper interface class,method name,paramters,and sqlSession.
package util;
import java.lang.reflect.Method;
import java.text.DateFormat;
import java.time.LocalDateTime;
import java.time.format.DateTimeFormatter;
import java.util.Date;
import java.util.List;
import java.util.Locale;
import java.util.regex.Matcher;
import org.apache.ibatis.binding.MapperMethod.MethodSignature;
import org.apache.ibatis.mapping.BoundSql;
import org.apache.ibatis.mapping.MappedStatement;
import org.apache.ibatis.mapping.ParameterMapping;
import org.apache.ibatis.reflection.MetaObject;
import org.apache.ibatis.session.Configuration;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.type.TypeHandlerRegistry;
import org.springframework.util.CollectionUtils;
/**
* #author zwxbest - 19-4-25
*/
public class SqlUtil {
public static String showSql(SqlSession sqlSession, Class mapperInterface, String methodName,
Object[] params) {
Configuration configuration = sqlSession.getConfiguration();
MappedStatement ms = configuration.getMappedStatement(
mapperInterface.getName() + "." + methodName);
Method sqlMethod = null;
//find method equals methodName
for (Method method : mapperInterface.getDeclaredMethods()) {
if (method.getName().equals(methodName)) {
sqlMethod = method;
break;
}
}
if (sqlMethod == null) {
throw new RuntimeException("mapper method is not found");
}
MethodSignature method = new MethodSignature(configuration, mapperInterface, sqlMethod);
Object paramObject = method.convertArgsToSqlCommandParam(params);
BoundSql boundSql = ms.getBoundSql(paramObject);
Object parameterObject = boundSql.getParameterObject();
List<ParameterMapping> parameterMappings = boundSql
.getParameterMappings();
String sql = boundSql.getSql().replaceAll("[\\s]+", " ");
if (!CollectionUtils.isEmpty(parameterMappings) && parameterObject != null) {
TypeHandlerRegistry typeHandlerRegistry = configuration
.getTypeHandlerRegistry();
if (typeHandlerRegistry.hasTypeHandler(parameterObject.getClass())) {
sql = sql.replaceFirst("\\?",
Matcher.quoteReplacement(getParameterValue(parameterObject)));
} else {
MetaObject metaObject = configuration.newMetaObject(
parameterObject);
for (ParameterMapping parameterMapping : parameterMappings) {
String propertyName = parameterMapping.getProperty();
if (metaObject.hasGetter(propertyName)) {
Object obj = metaObject.getValue(propertyName);
sql = sql
.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
} else if (boundSql.hasAdditionalParameter(propertyName)) {
Object obj = boundSql.getAdditionalParameter(propertyName);
sql = sql
.replaceFirst("\\?", Matcher.quoteReplacement(getParameterValue(obj)));
} else {
sql = sql.replaceFirst("\\?", "missing");
}
}
}
}
return sql;
}
/**
* if param's type is `String`,add single quotation<br>
*
* if param's type is `datetime`,convert to string and quote <br>
*/
private static String getParameterValue(Object obj) {
String value = null;
if (obj instanceof String) {
value = "'" + obj.toString() + "'";
} else if (obj instanceof Date) {
DateFormat formatter = DateFormat
.getDateTimeInstance(DateFormat.DEFAULT, DateFormat.DEFAULT, Locale.CHINA);
value = "'" + formatter.format(new Date()) + "'";
} else if (obj instanceof LocalDateTime) {
value = "\'" + ((LocalDateTime) obj)
.format(DateTimeFormatter.ofPattern("yyyy-MM-dd HH:mm:ss")) + "\'";
} else {
if (obj != null) {
value = obj.toString();
} else {
value = "";
}
}
return value;
}
}
call example
sqlSession is injected by Spring .
#Autowired
private SqlSession sqlSession;
String sql = SqlUtil
.showSql(sqlSession, PromotionCodeMapper.class, "selectByPromotionCodeForUpdate",
new Object[]{"111"});
log.warn(sql);
public static void main(String[] args) throws Exception {
String script = "<script>select * from table where 1 = 1<if test='id != null'>and id = ${id} </if></script>";
System.out.println(buildSql(script));
}
private static String buildSql(String script) {
LanguageDriver languageDriver = new XMLLanguageDriver();
Configuration configuration = new Configuration();
SqlSource sqlSource = languageDriver.createSqlSource(configuration, script, Object.class);
Map<String, String> parameters = new HashMap<>();
parameters.put("id", "1");
BoundSql boundSql = sqlSource.getBoundSql(parameters);
return boundSql.getSql();
}
use ${id} instead of #{id}
result is: select * from table where 1 = 1 and id = 1
Just to add to Bogdan's correct answer: You need to pass a JavaBean to getBoundSql() with getter's for your interface parameters, if you're interface has a more complex signature.
Let's assume you want to query the user based on the login number and/or the user name. Your interface might look like this:
package pack.test;
public interface UserService {
// using a different sort of parameter to show some dynamic SQL
public User getUser(#Param("number") int loginNumber, #Param("name") String name);
}
I'm leaving out the Mapper code since it's irrelevant for this discussion, but your code in AppTester should become:
[...]
final String name = "Andy";
User user = userService.getUser(i, name);
System.out.println("Retreived user: " + user.getName() + " " + user.getLogin());
// must mimic the internal statement key for the mapper and method you are calling
MappedStatement ms = session.getConfiguration().getMappedStatement(UserService.class.getName() + ".getUser");
BoundSql boundSql = ms.getBoundSql(new Object() {
// provide getters matching the #Param's in the interface declaration
public Object getNumber() {
return i;
}
public Object getName() {
return name;
}
});
System.out.println("SQL used: " + boundSql.getSql());
System.out.println();
[...]

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