Jsf 2.2.1, Backing beans cannot be bound to xhtml pages

Jsf 2.2.1, Backing beans cannot be bound to xhtml pages - java

I'm trying to develop a simple Jsf 2.2.1 application. I have looked through some pages and found sample applications. I wanted to try one of those samples. I set every dependencies and annotations; however, the backing bean is not working. What I wanted to do is to show some text fields via bean on the Jsf page and render some input texts. Jsf tags are working correctly but the bean values are not shown on the page. In the page I have an input text area and a command button. These components are shown on the page but I feed some text and press the command button I encounter the following problem. I am building the app with "mvn clean package" and then deploying it on Tomcat 7.x.
Error:
serverError: class javax.el.PropertyNotFoundException Target Unreachable, identifier 'helloWorld' resolved to null
In the followings I am sharing all my files.
web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<web-app id="WebApp_ID" version="2.5"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<display-name>helloworld</display-name>
<welcome-file-list>
<welcome-file>home.xhtml</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>Faces Servlet</servlet-name>
<servlet-class>javax.faces.webapp.FacesServlet</servlet-class>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Faces Servlet</servlet-name>
<url-pattern>*.xhtml</url-pattern>
</servlet-mapping>
<context-param>
<param-name>javax.faces.PROJECT_STAGE</param-name>
<param-value>Development</param-value>
</context-param>
pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.test</groupId>
<artifactId>helloworld</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>helloworld Maven Webapp</name>
<url>http://maven.apache.org</url>
<dependencies>
<dependency>
<groupId>junit</groupId>
<artifactId>junit</artifactId>
<version>3.8.1</version>
<scope>test</scope>
</dependency>
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-api</artifactId>
<version>2.2.1</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>com.sun.faces</groupId>
<artifactId>jsf-impl</artifactId>
<version>2.2.1</version>
<scope>compile</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
</dependency>
<dependency>
<groupId>javax.el</groupId>
<artifactId>el-api</artifactId>
<version>2.2</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>org.glassfish.web</groupId>
<artifactId>el-impl</artifactId>
<version>2.2</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<finalName>helloworld</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.3.1</version>
<configuration>
<source>1.5</source>
<target>1.5</target>
</configuration>
</plugin>
</plugins>
</build>
<repositories>
<repository>
<id>maven2-repository.dev.java.net</id>
<name>java.net Repository for Maven</name>
<url>http://download.java.net/maven/2</url>
</repository>
</repositories>
Java Beans:
HelloWorld.java
import javax.faces.bean.ManagedBean;
import javax.faces.bean.ManagedProperty;
import javax.faces.bean.SessionScoped;
#ManagedBean(name="helloWorld")
#SessionScoped
public class HelloWorld {
private String name="Zaman Safari";
#ManagedProperty(value = "#{demoService}")
private Service service;
public HelloWorld(){
System.out.println("HELLOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOO");
}
public String getName(){
return name;
}
public void setName(String name){
this.name = name;
}
public void setService(Service service){
this.service = service;
}
public String getReverse(){
return service.reverse(name);
}
}
Service.java:
import javax.faces.bean.ApplicationScoped;
import javax.faces.bean.ManagedBean;
#ManagedBean(name="demoService")
#ApplicationScoped
public class Service {
public String reverse(String name) {
return new StringBuffer(name).reverse().toString().toLowerCase();
}
}
What exactly am I missing in my files?

PropertyNotFoundException mean there is no getter/setter property method in your backing bean.
HelloWorldBean.java
#ManagedBean(name="HelloWorldBean")
public calss HelloWorldBean {
private String getHelloWorld() {
return "Hello World!";
}
}
mypage
<h:outputText value="#{HelloWorldBean.helloWorld}"/>

Related

Wildfly server running, but returning 404 error Not found no matter what I do

I followed a REST API | Web service tutorial on the web and got stuck midway. When I run the server it setups successfully, shows that its running at http://localhost:8080/ as well but as soon as I try to access different servlets, the page reloads and returns with 404 Error Not found. I tried downloading earlier versions of wildfly with no avail. The paths I tried were /demorest, /webapi, /myresources and they were used in conjunction as well.
What could be the problem?
package com.david.demorest;
import jakarta.ws.rs.GET;
import jakarta.ws.rs.Path;
import jakarta.ws.rs.Produces;
import jakarta.ws.rs.core.MediaType;
#Path("myresource")
public class MyResource {
#GET
#Produces(MediaType.TEXT_PLAIN)
public String getIt() {
return "Got it!";
}
}
<?xml version="1.0" encoding="UTF-8"?>
<!-- This web.xml file is not required when using Servlet 3.0 container,
see implementation details http://jersey.java.net/nonav/documentation/latest/jax-rs.html -->
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>Jersey Web Application</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>com.david.demorest</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey Web Application</servlet-name>
<url-pattern>/webapi/*</url-pattern>
</servlet-mapping>
</web-app>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.david</groupId>
<artifactId>demorest</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>demorest</name>
<build>
<finalName>demorest</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.1</version>
<inherited>true</inherited>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey</groupId>
<artifactId>jersey-bom</artifactId>
<version>${jersey.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-servlet-core</artifactId>
<!-- use the following artifactId if you don't need servlet 2.x compatibility -->
<!-- artifactId>jersey-container-servlet</artifactId -->
</dependency>
<dependency>
<groupId>org.glassfish.jersey.inject</groupId>
<artifactId>jersey-hk2</artifactId>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-binding</artifactId>
</dependency>
</dependencies>
<properties>
<jersey.version>3.0.4</jersey.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
</project>

It's likely that the tutorial is written to deploy to Tomcat. Wildfly has everything you need for JaxRS built in.
To get started you will need three files. First, you need a class that extends javax.ws.rs.core.Application. It can be in any package you'd like:
import javax.ws.rs.ApplicationPath;
import javax.ws.rs.core.Application;
#ApplicationPath("/rest")
public class RestApplicationConfig extends Application {
// intentionally empty
}
Next, you need your service. The one you show should work though I'd have my Path start with a forward slash like #Path("/myresource"). Lastly, you need a pom.xml that produces a war file. I haven't tested yours but I have one that looks like:
<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<artifactId>jaxrs-simple-sample</artifactId>
<groupId>com.hotjoe.jaxrs</groupId>
<version>1.0-SNAPSHOT</version>
<packaging>war</packaging>
<properties>
<maven.compiler.source>11</maven.compiler.source>
<maven.compiler.target>11</maven.compiler.target>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<failOnMissingWebXml>false</failOnMissingWebXml>
</properties>
<dependencies>
<dependency>
<groupId>javax</groupId>
<artifactId>javaee-api</artifactId>
<version>8.0.1</version>
<scope>provided</scope>
</dependency>
</dependencies>
<build>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-war-plugin</artifactId>
<version>3.3.2</version>
</plugin>
</plugins>
</build>
</project>
That I just verified works. Once you have all of this you can produce a war file that can be dropped into $WILDFLY_HOME/standalone/deployments and Wildfly will run it. But you need to watch the URL. As defined in my pom.xml this will create a war file named jaxrs-simple-sample-1.0-SNAPSHOT.war and this file name becomes part of the URL. In this example, the URL to your service would be http://localhost:8080/jaxrs-simple-sample-1.0-SNAPSHOT/rest/myresource. The rest part of that comes from the #ApplicationPath defined. But the other part comes from the name of the war. If you don't like that, you can add one more Wildfly specific file:
<?xml version="1.0" encoding="UTF-8"?>
<jboss-web>
<context-root>myapp</context-root>
</jboss-web>
This file, in a standard Maven environment, would be named jboss-web.xml and would be placed in src/main/webapp/WEB-INF. This would change the above URL to http://localhost:8080/myapp/rest/myresource.

Issue on running a JAVA 13 JAX-RS project in Tomcat 9

I'm working on this simple project and have this problem:
HTTP Status 404 – Not Found
Type Status Report
Message /RestTestThree/myService/Calculator/
Description The origin server did not find a current representation for the target resource or is not willing to disclose that one exists.
Apache Tomcat/9.0.30
I use this setting: JDK 13, Eclipse 2019-12, Tomcat 9.
I tried different URLs and I hope this one is the correct one:
http://localhost:8080/RestTestThree/myService/Calculator/
I tried both model 3 and 4. Tried different dependencies and versions.
When trying to run this project, at some point the Tomcat even won't start, giving the error
Server Tomcat v9.0 Server at localhost failed to start.
My files are as follows.
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 https://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.RestTestThree</groupId>
<artifactId>RestTestThree</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<build>
<sourceDirectory>src</sourceDirectory>
<plugins>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<version>3.8.0</version>
<configuration>
<release>13</release>
</configuration>
</plugin>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.2.3</version>
<configuration>
<warSourceDirectory>WebContent</warSourceDirectory>
</configuration>
</plugin>
</plugins>
</build>
<dependencies>
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-bundle</artifactId>
<version>1.17</version>
</dependency>
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-server</artifactId>
<version>1.17</version>
</dependency>
<dependency>
<groupId>com.sun.jersey</groupId>
<artifactId>jersey-core</artifactId>
<version>1.17</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>2.1.2</version>
</dependency>
<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.1</version>
</dependency>
</dependencies>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
id="WebApp_ID" version="3.0">
<display-name>RestTestThree</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>Jersey Web Application</servlet-name>
<servlet-class>com.sun.jersey.spi.container.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>com.sun.jersey.config.property.packages</param-name>
<param-value>com.Calculator</param-value> <!--comma separated packages -->
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Simple REST Service</servlet-name>
<url-pattern>/myService/*</url-pattern>
</servlet-mapping>
Calculator.java
package com;
import javax.ws.rs.*;
import javax.ws.rs.core.MediaType;
#Path("/Calculator")
public class Calculator
{
#GET
#Path("/")
#Produces(MediaType.TEXT_PLAIN)
public String hello()
{
return "Working...";
}
#GET
#Path("/Add")
#Produces(MediaType.TEXT_PLAIN)
public String add()
{
return "<div>Sum = 10</div>";
}
}

I had the same problem. After downgrade java 13 to 11 all work perfect. Need convert project to 11 some.

Java 1.8, tomcat 8.5, Jersey 2 - Can't make it work

I went over everything, even made some changes, fixed some problems but still the server sends back 404 even though tomcat itself is up and running. Following is what I did:
pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.resty</groupId>
<artifactId>resty</artifactId>
<version>0.0.1-SNAPSHOT</version>
<packaging>war</packaging>
<repositories>
<repository>
<id>maven2-repository.java.net</id>
<name>Java.net Repository for Maven</name>
<url>http://download.java.net/maven/2/</url>
<layout>default</layout>
</repository>
</repositories>
<dependencies>
<!-- JAX-RS -->
<dependency>
<groupId>javax.ws.rs</groupId>
<artifactId>javax.ws.rs-api</artifactId>
<version>2.0.1</version>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-servlet</artifactId>
<version>2.25.1</version>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.core</groupId>
<artifactId>jersey-server</artifactId>
<version>2.25.1</version>
</dependency>
<dependency>
<groupId>org.glassfish.jersey.core</groupId>
<artifactId>jersey-client</artifactId>
<version>2.25.1</version>
</dependency>
</dependencies>
<build>
<finalName>resty</finalName>
<plugins>
<plugin>
<artifactId>maven-war-plugin</artifactId>
<version>3.0.0</version>
</plugin>
<plugin>
<artifactId>maven-compiler-plugin</artifactId>
<configuration>
<source>1.8</source>
<target>1.8</target>
</configuration>
</plugin>
</plugins>
</build>
</project>
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns="http://java.sun.com/xml/ns/javaee" xmlns:web="http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd"
xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_3_0.xsd"
version="3.0">
<display-name>resty</display-name>
<welcome-file-list>
<welcome-file>index.html</welcome-file>
<welcome-file>index.htm</welcome-file>
<welcome-file>index.jsp</welcome-file>
<welcome-file>default.html</welcome-file>
<welcome-file>default.htm</welcome-file>
<welcome-file>default.jsp</welcome-file>
</welcome-file-list>
<servlet>
<servlet-name>jersey-serlvet</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>com.resty</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>jersey-serlvet</servlet-name>
<url-pattern>/resty/*</url-pattern>
</servlet-mapping>
</web-app>
Resty.java
package com.resty;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
#Path("/resty")
public class Resty {
#GET
#Produces(MediaType.APPLICATION_JSON)
#Path("/example")
public String getExample() {
return "{\"result\":\"blah\"}";
}
}
I'm sure I'm missing something but I just can't figure out what it is. When run as - running on server, eclipse opens this url: http://localhost:9090/Resty/ but I see 404. I tried adding more resty/ to the url and also /example (see code above) but all gives 404.
What am I missing?

you are using <url-pattern>/resty/*</url-pattern> in web.xml and using #Path("/resty") in class for class mapping, and use url http://localhost:9090/Resty/ that is wrong. you need to use <url-pattern>/*</url-pattern>. and url will be http://localhost:9090/resty/
you can also use anything into <url-pattern>/*</url-pattern> which you want but you need to use this pattern before controller path in url.

REST: MessageBodyWriter not found for media type=text/plain

I am currently learning REST and I'm facing an error while calling a method. I am sure that it must be a simple configuration setting, but since I am absolutely new to learning REST, not able to figure it out.
web.xml
<?xml version="1.0" encoding="UTF-8"?>
<!-- This web.xml file is not required when using Servlet 3.0 container,
see implementation details http://jersey.java.net/nonav/documentation/latest/jax-rs.html -->
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>Jersey Web Application</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>org.mishra.dev.rahul.messenger</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey Web Application</servlet-name>
<url-pattern>/webapi/*</url-pattern>
</servlet-mapping>
</web-app>
pom.xml
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>org.mishra.dev.rahul</groupId>
<artifactId>messenger</artifactId>
<packaging>war</packaging>
<version>0.0.1-SNAPSHOT</version>
<name>messenger</name>
<build>
<finalName>messenger</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.5.1</version>
<inherited>true</inherited>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey</groupId>
<artifactId>jersey-bom</artifactId>
<version>${jersey.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-servlet-core</artifactId>
<!-- use the following artifactId if you don't need servlet 2.x compatibility -->
<!-- artifactId>jersey-container-servlet</artifactId -->
</dependency>
<!-- uncomment this to get JSON support -->
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-moxy</artifactId>
</dependency>
<!-- https://mvnrepository.com/artifact/org.glassfish.jersey.media/jersey-media-json-jackson -->
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-jackson</artifactId>
</dependency>
</dependencies>
<properties>
<jersey.version>2.26-b03</jersey.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
</project>
resource class:
package org.mishra.dev.rahul.messenger.resources;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
#Path("messages")
public class MessageResource {
#GET
#Produces(MediaType.TEXT_PLAIN)
public Person getMessages() {
return new Person("Rahul", 31);
}
}
class Person {
private String name;
private int age;
public Person(String name, int age) {
this.name = name;
this.age = age;
}
#Override
public String toString() {
return "Name: " + name + ", Age: " + age;
}
}
Facing an error while calling: http://localhost:8080/messenger/webapi/messages
Error:
Jun 09, 2017 7:19:01 PM org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor aroundWriteTo
SEVERE: MessageBodyWriter not found for media type=text/plain, type=class org.mishra.dev.rahul.messenger.resources.Person, genericType=class org.mishra.dev.rahul.messenger.resources.Person.
Now, if instead of returning Person object, if I return a plain string like "Hello World", I do not face any issues.
EDIT:
**Solution:**I was missing the default constructor in the Person class. After adding the default constructor, I can now return the string format of the Person object.
However having said that, if I change #Produces(MediaType.APPLICATION_JSON) and return return new Person("Rahul", 31), I just see an empty JSON. I am not sure why dont I see the Person object in JSON format.

Well, I was also facing the same issue and the thing that worked for me, in this case, was that I annotated the API returning the response with this
#Produces(MediaType.APPLICATION_JSON)
There is no need for you to define the setter unnecessarily as it breaks the mutability of the object.

I read the documentation of Jersey and I found out that I need to make two changes in my resource class:
Declare the default constructor
Define getters and setters for the instance variables.
Add the following dependency in pom.xml
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-jackson</artifactId>
</dependency>
Now after making these changes I am able to view the string and JSON format of the Person object.

How can I send a JSON object with Jersey in a Rest Service

I'm trying to make a restful service with jersey, for that I'm using the jersey example for a maven project. So this is what I got:
my pom.xml:
<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
<modelVersion>4.0.0</modelVersion>
<groupId>com.example</groupId>
<artifactId>simple-service-webapp</artifactId>
<packaging>war</packaging>
<version>1.0-SNAPSHOT</version>
<name>simple-service-webapp</name>
<build>
<finalName>simple-service-webapp</finalName>
<plugins>
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-compiler-plugin</artifactId>
<version>2.5.1</version>
<inherited>true</inherited>
<configuration>
<source>1.7</source>
<target>1.7</target>
</configuration>
</plugin>
</plugins>
</build>
<dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey</groupId>
<artifactId>jersey-bom</artifactId>
<version>${jersey.version}</version>
<type>pom</type>
<scope>import</scope>
</dependency>
</dependencies>
</dependencyManagement>
<dependencies>
<dependency>
<groupId>org.glassfish.jersey.containers</groupId>
<artifactId>jersey-container-servlet-core</artifactId>
<!-- use the following artifactId if you don't need servlet 2.x compatibility -->
<!-- artifactId>jersey-container-servlet</artifactId -->
</dependency>
<!-- uncomment this to get JSON support <dependency> <groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-moxy</artifactId> </dependency> -->
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>servlet-api</artifactId>
<version>2.5</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet.jsp</groupId>
<artifactId>jsp-api</artifactId>
<version>2.1</version>
<scope>provided</scope>
</dependency>
<dependency>
<groupId>javax.servlet</groupId>
<artifactId>jstl</artifactId>
<version>1.2</version>
</dependency>
<dependency>
<groupId>com.fasterxml.jackson.jaxrs</groupId>
<artifactId>jackson-jaxrs-json-provider</artifactId>
<version>2.6.0</version>
</dependency>
</dependencies>
<properties>
<jersey.version>2.19</jersey.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
</properties>
</project>
my web.xml:
<?xml version="1.0" encoding="UTF-8"?>
<!-- This web.xml file is not required when using Servlet 3.0 container,
see implementation details http://jersey.java.net/nonav/documentation/latest/jax-rs.html -->
<web-app version="2.5" xmlns="http://java.sun.com/xml/ns/javaee" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance" xsi:schemaLocation="http://java.sun.com/xml/ns/javaee http://java.sun.com/xml/ns/javaee/web-app_2_5.xsd">
<servlet>
<servlet-name>Jersey Web Application</servlet-name>
<servlet-class>org.glassfish.jersey.servlet.ServletContainer</servlet-class>
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>com.example</param-value>
</init-param>
<load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
<servlet-name>Jersey Web Application</servlet-name>
<url-pattern>/webapi/*</url-pattern>
</servlet-mapping>
</web-app>
the resource
package com.example;
import javax.ws.rs.GET;
import javax.ws.rs.Path;
import javax.ws.rs.PathParam;
import javax.ws.rs.Produces;
import javax.ws.rs.core.MediaType;
/**
* Root resource (exposed at "myresource" path)
*/
#Path("/myresource")
public class MyResource {
/**
* Method handling HTTP GET requests. The returned object will be sent
* to the client as "text/plain" media type.
*
* #return String that will be returned as a text/plain response.
*/
#GET
#Produces(MediaType.TEXT_PLAIN)
public String getIt() {
return "Got it!";
}
#Path( "complexObject/{name}" )
#GET
#Produces( { MediaType.APPLICATION_JSON } )
public ComplexObject complexObject( #PathParam( "name" ) String name ) {
return new ComplexObject(name);
}
}
The ComplexObject class is just a class with a string.
when I hit the url: http://localhost:8080/simple-service-webapp/webapi/myresource/
This work, I get "Got it!"
but when I hit on: http://localhost:8080/simple-service-webapp/webapi/myresource/complexObject/capo
I get this error on the console:
SEVERE: MessageBodyWriter not found for media type=application/json,
type=class com.example.ComplexObject, genericType=class
com.example.ComplexObject.
How can I fix this?

With this dependency
<dependency>
<groupId>com.fasterxml.jackson.jaxrs</groupId>
<artifactId>jackson-jaxrs-json-provider</artifactId>
<version>2.6.0</version>
</dependency>
You will still need to register the provider. You could register it individually
<init-param>
<param-name>jersey.config.server.provider.classnames</param-name>
<param-value>
com.fasterxml.jackson.jaxrs.json.JacksonJaxbJsonProvider
</param-value>
</init-param>
Or since the dependency also comes with Jackson ExceptionMappers, you might want to just have the whole package scanned (just add it to the list of packages)
<init-param>
<param-name>jersey.config.server.provider.packages</param-name>
<param-value>
com.example,
com.fasterxml.jackson.jaxrs.json
</param-value>
</init-param>
Another option, besides using the above dependency, is to use Jersey's "wrapper" dependency (which handle the registration of the of the providers, among a couple other things such as Jackson Entity Filtering. Just used
<dependency>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-jackson</artifactId>
</dependency>
With this dependency, do registration is required. It is automatically registered through Jersey's auto-discoverable feature

Develop Reference

Java is a programming language and computing platform first released by Sun Microsystems in 1995.

Jsf 2.2.1, Backing beans cannot be bound to xhtml pages - java

PropertyNotFoundException mean there is no getter/setter property method in your backing bean. HelloWorldBean.java #ManagedBean(name="HelloWorldBean") public calss HelloWorldBean { private String getHelloWorld() { return "Hello World!"; } } mypage <h:outputText value="#{HelloWorldBean.helloWorld}"/>

Related

Wildfly server running, but returning 404 error Not found no matter what I do

Issue on running a JAVA 13 JAX-RS project in Tomcat 9

Java 1.8, tomcat 8.5, Jersey 2 - Can't make it work

REST: MessageBodyWriter not found for media type=text/plain

How can I send a JSON object with Jersey in a Rest Service

Categories

Resources