Rest API | Web Service Tutorial

I'm using jersey v2.29

I'm getting 500 error when return java object as XML... but no any error on console.. But i can get string if return string

what are the prerequisites for restful service in java

i am getting error 404 --the origin server did not find a current representation for the target resource or is not willing to disclose that one exists

Thank you sir for this tutorial

While running time showing (java.lang.ClassNotFoundException:jakarta.servlet.filter) but I have added related dependencies also still not solving the problem...

i dont understand that why he have to talk about servlet in everything instead of the topic of the tutorial,.I was referring spring boot there also he lecture about servlet n all , then i switched to this here also the same thing, everybody here is not from software background here, Please understand this, I have learnt java only with the help of telusko, but while learning advance , its disturbing that he talks more about the topics which everybody might not understand

Please Which app do you use for your screen recording?

this is so cringe-worthy

Can you provide tutorials in Telugu step by step ...from spring framework

that is tricky . thanks for successfully video

nice content

nice comment

"because I love Jason"🙃

@RestController
@RequestMapping(value = "/employee")
public class EmployeeController {

@Autowired
private EmployeeRep employeeRep;

@GetMapping("/one")
public Map<String, Long> maleAndFemaleEmployees() {
List<Employee> noOfMaleAndFemaleEmployees = employeeRep.findAll();

Map<String, Long> collect = noOfMaleAndFemaleEmployees.stream()
.collect(Collectors.groupingBy(Employee::getGender, Collectors.counting()));
return collect;

}

@GetMapping("/two")
public Stream<String> findAllEmpDeptDistinct() {
List<Employee> findAll = employeeRep.findAll();

Stream<String> distinct = findAll.stream().map(app -> app.getDept()).distinct();

return distinct;

}

@GetMapping("/three")
public Map<String, Double> avgAgeOfMaleAndFemale() {
List<Employee> avgAgeOfMaleAndFemaleEmployees = employeeRep.findAll();

Map<String, Double> collect = avgAgeOfMaleAndFemaleEmployees.stream()
.collect(Collectors.groupingBy(Employee::getGender, Collectors.averagingDouble(Employee::getAge)));
return collect;

}

@GetMapping("/four")
public Optional<Employee> highPaidEmployee() {
List<Employee> highestPaidDetailFull = employeeRep.findAll();

Optional<Employee> max = highestPaidDetailFull.stream()
.collect(Collectors.maxBy(Comparator.comparingDouble(Employee::getSalary)));
return max;
}

@GetMapping("/five")
public ResponseEntity<String> highestPaidEmployee() {
List<Employee> highestPaid = employeeRep.findAll();

Optional<Employee> max = highestPaid.stream().max(Comparator.comparing(Employee::getSalary));

if (max.isPresent()) {
Employee employee = max.get();
String name = employee.getName();
String department = employee.getDept();

String response = "Highest Paid Employee: " + name + " (Department: " + department + ")";
return ResponseEntity.ok(response);
} else {
return ResponseEntity.notFound().build();
}
}

@GetMapping("/six")
public Stream<String> joinedafter2015() {
List<Employee> findAll = employeeRep.findAll();

Stream<String> map = findAll.stream().filter(te -> te.getYearOfJoining() > 2015).map(Employee::getName);
return map;
}

@GetMapping("/seven")
public Map<String, Long> employeeCountByDepartment() {
List<Employee> countByDepartment = employeeRep.findAll();

Map<String, Long> collect = countByDepartment.stream()
.collect(Collectors.groupingBy(Employee::getDept, Collectors.counting()));

return collect;

}

@GetMapping("/eight")
public Map<String, Double> avgSalaryOfDepartments() {
List<Employee> avgSalaryOfDepts = employeeRep.findAll();

Map<String, Double> collect = avgSalaryOfDepts.stream()
.collect(Collectors.groupingBy(Employee::getDept, Collectors.averagingDouble(Employee::getSalary)));

return collect;

}

@GetMapping("/nine")
public Optional<Employee> youngestMaleEmployeeInProductDevelopment() {
List<Employee> youngestMaleEmployeeInProductDeve = employeeRep.findAll();

Optional<Employee> max = youngestMaleEmployeeInProductDeve.stream()
.filter(te -> te.getGender().equals("Male") && te.getDept().equals("Product Development"))
.min(Comparator.comparing(Employee::getAge));

return max;

}

@GetMapping("/ten")
public Optional<Employee> seniorMostEmployee() {
List<Employee> seniorEmployee = employeeRep.findAll();

Optional<Employee> collect = seniorEmployee.stream()
.collect(Collectors.minBy(Comparator.comparing(Employee::getYearOfJoining)));
return collect;

}

@GetMapping("/eleven")
public Map<String, Long> countMaleFemaleEmployeesInSalesMarketing() {
List<Employee> countMaleFemaleEmpInSalesMarketing = employeeRep.findAll();

Map<String, Long> collect = countMaleFemaleEmpInSalesMarketing.stream()
.filter(te -> te.getDept().equals("Sales And Marketing"))
.collect(Collectors.groupingBy(Employee::getGender, Collectors.counting()));
return collect;

}

@GetMapping("/twelve")
public Map<String, Double> avgSalaryOfMaleAndFemaleEmployees() {
List<Employee> avgSalaryOfMaleAndFemaleEmp = employeeRep.findAll();

Map<String, Double> collect = avgSalaryOfMaleAndFemaleEmp.stream()
.collect(Collectors.groupingBy(Employee::getGender, Collectors.averagingDouble(Employee::getSalary)));
return collect;

}

@GetMapping("/thirteen")
public Map<String, List<String>> employeeListByDepartment() {
List<Employee> findAll = employeeRep.findAll();

Map<String, List<String>> collect = findAll.stream().collect(
Collectors.groupingBy(Employee::getDept, Collectors.mapping(Employee::getName, Collectors.toList())));

return collect;

}

@GetMapping("/fourteen")
public String employeeSalarySumAndAvg() {

List<Employee> empSalarySumAndAvg = employeeRep.findAll();

DoubleSummaryStatistics collect = empSalarySumAndAvg.stream()
.collect(Collectors.summarizingDouble(Employee::getSalary));

return "Total Salary = " + collect.getSum() + ", Average Salary = " + collect.getAverage();

}

@GetMapping("/fifteen")
public ResponseEntity<String> partitionEmployeesByAge() {
List<Employee> partitionEmployeesByAge25OldAnd25Young = employeeRep.findAll();

Map<Boolean, List<Employee>> collect = partitionEmployeesByAge25OldAnd25Young.stream()
.collect(Collectors.partitioningBy(te -> te.getAge() > 25));

Set<Entry<Boolean, List<Employee>>> entrySet = collect.entrySet();

String olderEmployeesResponse = "Employees older than 25 years: ";
String youngerEmployeesResponse = "Employees younger than or equal to 25 years: ";

for (Entry<Boolean, List<Employee>> entry : entrySet) {
List<Employee> list = entry.getValue();

for (Employee employee : list) {
String employeeName = employee.getName() + ", ";
if (entry.getKey()) {
olderEmployeesResponse += employeeName;
} else {
youngerEmployeesResponse += employeeName;
}
}
}

String finalResponse = olderEmployeesResponse + "\n" + youngerEmployeesResponse;

return ResponseEntity.ok(finalResponse);
}

@GetMapping("/sixteen")
public ResponseEntity<String> oldestEmployee() {

List<Employee> oldestEmp = employeeRep.findAll();
Optional<Employee> max = oldestEmp.stream().max(Comparator.comparing(Employee::getAge));

if (max.isPresent()) {
Employee employee = max.get();
String dept = employee.getDept();
int age = employee.getAge();

String response1 = "Department : " + dept;
String response2 = "Age : " + age;

String responseBody = response1 + "\n" + response2;

return ResponseEntity.ok(responseBody);
} else {
return ResponseEntity.notFound().build(); // Or any appropriate response for no employees found
}

}

@GetMapping("/seventeen")
public List<String> findAllEmpNamesStartWithA() {
List<Employee> findAll = employeeRep.findAll();

List<String> collect = findAll.stream().filter(te -> te.getName().startsWith("A")).map(Employee::getName)
.collect(Collectors.toList());

return collect;

}

@GetMapping("/eighteen")
public String findAllEmpDeptCount() {
List<Employee> findAll = employeeRep.findAll();

long count = findAll.stream().map(app -> app.getDept()).distinct().count();

return "Total Department : - " + count;

}

@GetMapping("/ninteen")
public String findAllEmpCount() {
List<Employee> allEmpCount = employeeRep.findAll();

Long count = allEmpCount.stream().collect(Collectors.counting());

return "Total Employees: " + count;

}

}

In this video details of RestAPI is just 10% and remaining 90% consist of jersey project creation, Spring project creation, jdbc etc.

Awesome explanation, seeing this in 2023

Hi scuse me for my english. I tried to follow the tutorial but this error appears as soon as I invoke the rest "java.lang.NoClassDefFoundError: jakarta/servlet/Filter".
Tomcat 8 and java 1.8
The configuration is in the pom:

<properties>
<jersey.version>3.1.3</jersey.version>
<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
<war.mvn.plugin.version>3.4.0</war.mvn.plugin.version>
</properties>


<dependencies>
<dependencies>
<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>

<dependencies>
<groupId>org.glassfish.jersey.inject</groupId>
<artifactId>jersey-hk2</artifactId>
</dependency>


<!-- uncomment this to get JSON support
<dependencies>
<groupId>org.glassfish.jersey.media</groupId>
<artifactId>jersey-media-json-binding</artifactId>
</dependency>
-->
</dependencies>

web.xml:
<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.telusko.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>

Help me Thaks

I am using tomcat10 and jersey version 3.1.3 but not able to avoid this error - SEVERE: MessageBodyWriter not found for media type=application/xml, type=class com.jersey.demorest.Alien, genericType=class com.jersey.demorest.Alien.

You helped me so much

the XmlRootElement annotation is not working

any help

Thank you so much for your very useful videos.. Keep up the good work !

❤

Sir please share video on Selenium Webdriver, TestNg,Jenkins, Maven, RestAssured

please update this video quality is bad

Your explanation is great, but I have a question: how can I build a front-end for a web page using this data?

❤ You made this complex topic so easy. Thank you!!

java.lang.ClassNotFoundException: jakarta.servlet.Filter
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1407)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1215)
at java.base/java.lang.ClassLoader.defineClass1(Native Method)
at java.base/java.lang.ClassLoader.defineClass(ClassLoader.java:1017)
at java.base/java.security.SecureClassLoader.defineClass(SecureClassLoader.java:150)
at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:2478)
at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:870)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1371)
at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1215)
at org.apache.catalina.core.DefaultInstanceManager.loadClass(DefaultInstanceManager.java:538)
at org.apache.catalina.core.DefaultInstanceManager.loadClassMaybePrivileged(DefaultInstanceManager.java:519)
at org.apache.catalina.core.DefaultInstanceManager.newInstance(DefaultInstanceManager.java:149)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1070)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1010)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:4957)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5264)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1396)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1386)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:145)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:919)
at org.apache.catalina.core.StandardHost.startInternal(StandardHost.java:835)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1396)
at org.apache.catalina.core.ContainerBase$StartChild.call(ContainerBase.java:1386)
at java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)
at org.apache.tomcat.util.threads.InlineExecutorService.execute(InlineExecutorService.java:75)
at java.base/java.util.concurrent.AbstractExecutorService.submit(AbstractExecutorService.java:145)
at org.apache.catalina.core.ContainerBase.startInternal(ContainerBase.java:919)
at org.apache.catalina.core.StandardEngine.startInternal(StandardEngine.java:263)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
at org.apache.catalina.core.StandardService.startInternal(StandardService.java:432)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
at org.apache.catalina.core.StandardServer.startInternal(StandardServer.java:927)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:183)
at org.apache.catalina.startup.Catalina.start(Catalina.java:772)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:77)
at java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.base/java.lang.reflect.Method.invoke(Method.java:568)
at org.apache.catalina.startup.Bootstrap.start(Bootstrap.java:345)
at org.apache.catalina.startup.Bootstrap.main(Bootstrap.java:476) I am getting this error when i try to run the application how can i eliminate this . I tried so many times but error not rectified please Solve this Error

What do we have to learn before learning rest API? Is having knowledge on java is enough for learning rest api

I get this error. Can anyone guide me how to solve this,
java.lang.ClassNotFoundException: com.mysql.jdbc.Driver

Can you please share the source code for this project

why my pom.xml showing error in first line

please solve it sir

Amazing! sir

Jun 13, 2024 11:03:11 AM org.glassfish.jersey.message.internal.WriterInterceptorExecutor$TerminalWriterInterceptor aroundWriteTo
SEVERE: MessageBodyWriter not found for media type=application/xml, type=class com.RestDemo.Student, genericType=class com.RestDemo.Student.



i keep having this error just just can't fix it, i tried changing dependencies but it just dosen't work, please help

For people stuck at 41.10, copy paste below lines in pom.xml

<dependency>
<groupId>javax.xml.bind</groupId>
<artifactId>jaxb-api</artifactId>
<version>2.3.1</version>
</dependency>
<dependency>
<groupId>com.sun.xml.bind</groupId>
<artifactId>jaxb-impl</artifactId>
<version>2.3.4</version>
</dependency>
<dependency>
<groupId>org.glassfish.jaxb</groupId>
<artifactId>jaxb-runtime</artifactId>
<version>4.0.0</version>
</dependency>

if anyone facing an exception of class not found for sql driver
set url as follows
"jdbc:mysql://localhost:3306/{your-database-name}?useSSL=false&serverTimezone=UTC";

set usessl = false and then run it

unable to find jersey in maven project help!!
🥲

Aliens Assemble!!

Hello sir can you update this project on you git repo, I searched but it is not available.

sir i just want to confirm is this playlist video are good for learning today , as you can see i am 5 year late to learn about java, restapi, springboot , many updates had done in these languages, i am little bit confuse because as i do according to your videos many option are not found many error come , i don't found exact way to learn about restapi