What's the output of the run with this class & JSON?
(*Chris*)
On Thu, Oct 11, 2012 at 10:52 AM, Shaun Lim <[email protected]> wrote:
> Hi Chris,
>
> I did start off with a List<String> implementation but started changing
> stuff around in futile attempts to get something working. Anyway I tried
> your suggestion, and am still getting the same error:
>
> //I've a whole bunch of different fields here cause i was testing various
> things, but "arrayListStr" follows your recommendation
>
> public class Test {
> private String name;
> private String description;
> private List countries;
>
> private String[] array;
>
> private TestChild testChild;
> private ArrayList arrayList;
> private List<String> arrayListStr;
>
> public Test() {
> arrayList = new ArrayList();
> arrayListStr = new ArrayList<String>();
> }
>
> public String getName() {
> return name;
> }
>
> public void setName(String name) {
> System.out.println("setting name");
> this.name = name;
> }
>
> public String getDescription() {
> System.out.println("getting desc");
> return description;
> }
>
> public void setDescription(String description) {
> System.out.println("settings description");
> this.description = description;
> }
>
> public List getCountries() {
> return countries;
> }
>
> public void setCountries(List countries) {
> System.out.println("settings countries");
> this.countries = countries;
> }
>
> public TestChild getTestChild() {
> return testChild;
> }
>
> public void setTestChild(TestChild testChild) {
> System.out.println("setting testchild");
> this.testChild = testChild;
> }
>
> public String[] getArray() {
> return array;
> }
>
> public void setArray(String[] array) {
> System.out.println("setting arr");
> this.array = array;
> }
>
> public ArrayList getArrayList() {
> return arrayList;
> }
>
> public void setArrayList(ArrayList arrayList) {
> System.out.println("setting arrlist");
> this.arrayList = arrayList;
> }
>
> public List<String> getArrayListStr() {
> return arrayListStr;
> }
>
> public void setArrayListStr(List<String> arrayListStr) {
> System.out.println("setting arrliststr");
> this.arrayListStr = arrayListStr;
> }
> }
>
> And the JSON:
>
> {"testChild": {"description":"kid"},"description":"whee", "name":
> "foo","array":["CA","SG"],"arrayListStr":["CA","SG"]}
>
> Thanks for your help!
>
> Shaun
>
> On Wed, Oct 10, 2012 at 11:33 PM, Chris Pratt <[email protected]
> >wrote:
>
> > You *might* need to initialize the countries array. I wouldn't be
> > surprised if internally the JSON library is doing a
> > getCountries().add("CA") and throwing a null pointer exception because
> > getCountries is returning a null.
> >
> > Also, you should really be programming to interfaces, not
> implementations.
> > Define your methods to take and return the List<String> interface instead
> > of the ArrayList<String> specific implementation and your programs will
> be
> > much more flexible and reusable in the future. See if this works better:
> > (*Chris*)
> >
> > public class Test {
> > private String name;
> > private String description;
> > private List<String> countries;
> >
> > public Test() {
> > countries = new ArrayList<>();
> > }
> >
> > public String getName() {
> > return name;
> > }
> >
> > public void setName(String name) {
> > this.name = name;
> > }
> >
> > public String getDescription() {
> > return description;
> > }
> >
> > public void setDescription(String description) {
> > this.description = description;
> > }
> >
> > public List<String> getCountries() {
> > return countries;
> > }
> >
> > public void setCountries(List<String> countries) {
> > this.countries = countries;
> > }
> > }
> >
> > On Wed, Oct 10, 2012 at 11:23 PM, Shaun Lim <[email protected]>
> > wrote:
> >
> > > My entity class:
> > >
> > > import java.util.ArrayList;
> > >
> > >
> > > public class Test {
> > > private String name;
> > > private String description;
> > > private ArrayList<String> countries;
> > >
> > > public Test() {
> > >
> > > }
> > >
> > > public String getName() {
> > > return name;
> > > }
> > >
> > > public void setName(String name) {
> > > this.name = name;
> > > }
> > >
> > > public String getDescription() {
> > > return description;
> > > }
> > >
> > > public void setDescription(String description) {
> > > this.description = description;
> > > }
> > >
> > > public ArrayList<String> getCountries() {
> > > return countries;
> > > }
> > >
> > > public void setCountries(ArrayList<String> countries) {
> > > this.countries = countries;
> > > }
> > > }
> > >
> > > The JSON I'm trying to send:
> > >
> > > {"countries": ["CA", "SG"], "description":"whee", "name": "foo"}
> > >
> > > The error:
> > >
> > > 2345447 [http-bio-8080-exec-1] ERROR freemarker.runtime - Method
> > > public java.lang.String
> > >
> >
> org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int)
> > > threw an exception when invoked on net.sf.json.JSONException: Error
> > > while setting property=countries type interface java.util.List
> > >
> > > Method public java.lang.String
> > >
> >
> org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int)
> > > threw an exception when invoked on net.sf.json.JSONException: Error
> > > while setting property=countries type interface java.util.List
> > > The problematic instruction:
> > > ----------
> > > ==> ${msgs[0][0]} [on line 76, column 25 in
> > > org/apache/struts2/dispatcher/error.ftl]
> > > ----------
> > >
> > > Java backtrace for programmers:
> > > ----------
> > > freemarker.template.TemplateModelException: Method public
> > > java.lang.String
> > >
> >
> org.apache.commons.lang.exception.NestableRuntimeException.getMessage(int)
> > > threw an exception when invoked on net.sf.json.JSONException: Error
> > > while setting property=countries type interface java.util.List
> > > at
> > > freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:130)
> > > at
> > > freemarker.ext.beans.SimpleMethodModel.get(SimpleMethodModel.java:138)
> > > at
> > >
> >
> freemarker.core.DynamicKeyName.dealWithNumericalKey(DynamicKeyName.java:111)
> > > at
> > >
> >
> freemarker.core.DynamicKeyName._getAsTemplateModel(DynamicKeyName.java:90)
> > > at
> freemarker.core.Expression.getAsTemplateModel(Expression.java:89)
> > > at freemarker.core.Expression.getStringValue(Expression.java:93)
> > > at freemarker.core.DollarVariable.accept(DollarVariable.java:76)
> > > at freemarker.core.Environment.visit(Environment.java:210)
> > > at freemarker.core.MixedContent.accept(MixedContent.java:92)
> > > at freemarker.core.Environment.visit(Environment.java:210)
> > > at freemarker.core.IfBlock.accept(IfBlock.java:82)
> > > at freemarker.core.Environment.visit(Environment.java:210)
> > > at freemarker.core.IfBlock.accept(IfBlock.java:82)
> > > at freemarker.core.Environment.visit(Environment.java:210)
> > > at freemarker.core.MixedContent.accept(MixedContent.java:92)
> > > at freemarker.core.Environment.visit(Environment.java:210)
> > > at freemarker.core.Environment.process(Environment.java:190)
> > > at freemarker.template.Template.process(Template.java:237)
> > > at
> > > org.apache.struts2.dispatcher.Dispatcher.sendError(Dispatcher.java:797)
> > > at
> > >
> >
> org.apache.struts2.dispatcher.Dispatcher.serviceAction(Dispatcher.java:519)
> > > at
> > >
> >
> org.apache.struts2.dispatcher.ng.ExecuteOperations.executeAction(ExecuteOperations.java:77)
> > > at
> > >
> >
> org.apache.struts2.dispatcher.ng.filter.StrutsPrepareAndExecuteFilter.doFilter(StrutsPrepareAndExecuteFilter.java:91)
> > > at
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243)
> > > at
> > >
> >
> org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210)
> > > at
> > >
> >
> org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:224)
> > > at
> > >
> >
> org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
> > > at
> > >
> >
> org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:462)
> > > at
> > >
> >
> org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:164)
> > > at
> > >
> >
> org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:100)
> > > at
> > >
> org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:851)
> > > at
> > >
> >
> org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118)
> > > at
> > >
> >
> org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:405)
> > > at
> > >
> >
> org.apache.coyote.http11.Http11Processor.process(Http11Processor.java:278)
> > > at
> > >
> >
> org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:515)
> > > at
> > >
> >
> org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:300)
> > > at
> > >
> >
> java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886)
> > > at
> > >
> >
> java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908)
> > > at java.lang.Thread.run(Thread.java:680)
> > > Caused by: java.lang.NullPointerException
> > > at
> > >
> >
> freemarker.ext.beans.SimpleMemberModel.unwrapArguments(SimpleMemberModel.java:85)
> > > at
> > > freemarker.ext.beans.SimpleMethodModel.exec(SimpleMethodModel.java:106)
> > > ... 37 more
> > >
> > > Setting "name" and "description" without attempting to pass in
> > "countries"
> > > work - the values are successfully mapped.
> > >
> > > Using the following XML works too:
> > >
> > > <com.foo.bar.entity.Test>
> > > <countries>
> > > <string>SG</string>
> > > </countries>
> > > <description>testt</description>
> > > </com.foo.bar.entity.Test>
> > >
> >
>
