diff --git a/.mvn/wrapper/maven-wrapper.properties b/.mvn/wrapper/maven-wrapper.properties
index c954cec..4465bd9 100644
--- a/.mvn/wrapper/maven-wrapper.properties
+++ b/.mvn/wrapper/maven-wrapper.properties
@@ -1 +1 @@
-distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.3.9/apache-maven-3.3.9-bin.zip
+distributionUrl=https://repo1.maven.org/maven2/org/apache/maven/apache-maven/3.9.6/apache-maven-3.9.6-bin.zip
diff --git a/README.md b/README.md
index 2b09400..3897cfe 100644
--- a/README.md
+++ b/README.md
@@ -1,5 +1,5 @@
-# springboot-java8
-The project is made on spring boot. The project summarize the new features present in Java 8.
+# springboot-java15
+The project is made on spring boot. The project summarizes the features present in Java 8 through Java 15.
It contain list of harcoded topics list. You can call the apis's with POSTMAN to add,delete,update Topic list
In addition, it uses
1) Java 8 NIO methods
@@ -13,6 +13,8 @@ In addition, it uses
9) Default and Static methods in interface
10) Java 8 LocalDateTime API
11) Pattern
+12) Java 10+ local variable type inference (var)
+13) Java 15 text blocks
@@ -76,13 +78,12 @@ GET /datetime
### Prerequisites
-1) Java sdk
+1) Java 15 SDK
2) POSTMAN
### Installing
-
```
1) Download or clone
2) Import the project
@@ -129,6 +130,4 @@ https://dzone.com/articles/java-8-friday-goodies-new-new
## Authors
-* **Rehman Murad Ali**
-
-
+* **Rehman Murad Ali**
diff --git a/build.gradle b/build.gradle
index 09f1083..6839889 100644
--- a/build.gradle
+++ b/build.gradle
@@ -3,7 +3,7 @@ buildscript {
mavenCentral()
}
dependencies {
- classpath("org.springframework.boot:spring-boot-gradle-plugin:2.0.2.RELEASE")
+ classpath("org.springframework.boot:spring-boot-gradle-plugin:2.7.18")
}
}
@@ -14,19 +14,20 @@ apply plugin: 'org.springframework.boot'
apply plugin: 'io.spring.dependency-management'
bootJar {
- baseName = 'gs-spring-boot'
- version = '0.1.0'
+ archiveBaseName = 'gs-spring-boot'
+ archiveVersion = '0.1.0'
}
repositories {
mavenCentral()
}
-sourceCompatibility = 1.8
-targetCompatibility = 1.8
+sourceCompatibility = 15
+targetCompatibility = 15
dependencies {
- compile("org.springframework.boot:spring-boot-starter-web")
- testCompile("junit:junit")
+ implementation("org.springframework.boot:spring-boot-starter-web")
+ implementation("org.springframework.boot:spring-boot-starter-jdbc")
+ runtimeOnly("com.h2database:h2")
+ testImplementation("junit:junit")
}
-
diff --git a/gradle/wrapper/gradle-wrapper.properties b/gradle/wrapper/gradle-wrapper.properties
index a2ff3cc..03a8d13 100644
--- a/gradle/wrapper/gradle-wrapper.properties
+++ b/gradle/wrapper/gradle-wrapper.properties
@@ -3,4 +3,4 @@ distributionBase=GRADLE_USER_HOME
distributionPath=wrapper/dists
zipStoreBase=GRADLE_USER_HOME
zipStorePath=wrapper/dists
-distributionUrl=https\://services.gradle.org/distributions/gradle-4.6-bin.zip
+distributionUrl=https\://services.gradle.org/distributions/gradle-7.6.4-bin.zip
diff --git a/gradlew b/gradlew
old mode 100644
new mode 100755
diff --git a/mvnw b/mvnw
old mode 100644
new mode 100755
diff --git a/pom.xml b/pom.xml
index 63f5cbd..9e270a1 100644
--- a/pom.xml
+++ b/pom.xml
@@ -5,13 +5,13 @@
org.springframework
gs-spring-boot
- pom
+ jar
0.1.0
org.springframework.boot
spring-boot-starter-parent
- 2.0.2.RELEASE
+ 2.7.18
@@ -35,12 +35,20 @@
- 1.8
+ 15
+
+ org.apache.maven.plugins
+ maven-compiler-plugin
+ 3.8.1
+
+ 15
+
+
org.springframework.boot
spring-boot-maven-plugin
diff --git a/src/main/java/hello/Application.java b/src/main/java/hello/Application.java
index 7cf8faf..eed9f0a 100644
--- a/src/main/java/hello/Application.java
+++ b/src/main/java/hello/Application.java
@@ -25,19 +25,25 @@ public class Application implements CommandLineRunner {
public static void main(String[] args) {
- ApplicationContext ctx = SpringApplication.run(Application.class, args);
-
+ var ctx = SpringApplication.run(Application.class, args);
+
System.out.println("Let's inspect the beans provided by Spring Boot:");
-
- String[] beanNames = ctx.getBeanDefinitionNames();
+
+ var beanNames = ctx.getBeanDefinitionNames();
Arrays.sort(beanNames);
- for (String beanName : beanNames) {
+ for (var beanName : beanNames) {
System.out.println(beanName);
}
- RestTemplate restTemplate = new RestTemplate();
- Quote quote = restTemplate.getForObject("http://gturnquist-quoters.cfapps.io/api/random", Quote.class);
- log.info(quote.toString());
+ try {
+ var restTemplate = new RestTemplate();
+ var quote = restTemplate.getForObject("https://dummyjson.com/quotes/random", Quote.class);
+ if (quote != null) {
+ log.info(quote.toString());
+ }
+ } catch (Exception e) {
+ log.warn("Could not fetch quote from external service: {}", e.getMessage());
+ }
}
@@ -49,9 +55,15 @@ public RestTemplate restTemplate(RestTemplateBuilder builder) {
@Bean
public CommandLineRunner run(RestTemplate restTemplate) throws Exception {
return args -> {
- Quote quote = restTemplate.getForObject(
- "http://gturnquist-quoters.cfapps.io/api/random", Quote.class);
- log.info(quote.toString());
+ try {
+ var quote = restTemplate.getForObject(
+ "https://dummyjson.com/quotes/random", Quote.class);
+ if (quote != null) {
+ log.info(quote.toString());
+ }
+ } catch (Exception e) {
+ log.warn("Could not fetch quote from external service: {}", e.getMessage());
+ }
};
}
@@ -64,23 +76,26 @@ public void run(String... args) throws Exception {
log.info("Creating tables");
jdbcTemplate.execute("DROP TABLE customers IF EXISTS");
- jdbcTemplate.execute("CREATE TABLE customers(id SERIAL, first_name VARCHAR(255), last_name VARCHAR(255))");
-
- // Split up the array of whole names into an array of first/last names
- List splitUpNames = Arrays.asList("John Woo", "Jeff Dean", "Josh Bloch", "Josh Long")
+ jdbcTemplate.execute("""
+ CREATE TABLE customers(
+ id SERIAL,
+ first_name VARCHAR(255),
+ last_name VARCHAR(255)
+ )""");
+
+ List splitUpNames = List.of("John Woo", "Jeff Dean", "Josh Bloch", "Josh Long")
.stream()
- .map(name -> name.split(" "))
+ .map(name -> (Object[]) name.split(" "))
.collect(Collectors.toList());
- // Use a Java 8 stream to print out each tuple of the list
splitUpNames.forEach(name -> log.info(String.format("Inserting customer record for %s %s", name[0], name[1])));
- // Uses JdbcTemplate's batchUpdate operation to bulk load data
jdbcTemplate.batchUpdate("INSERT INTO customers(first_name, last_name) VALUES (?,?)", splitUpNames);
log.info("Querying for customer records where first_name = 'Josh':");
jdbcTemplate.query(
- "SELECT id, first_name, last_name FROM customers WHERE first_name = ?", new Object[]{"Josh"},
+ "SELECT id, first_name, last_name FROM customers WHERE first_name = ?",
+ new Object[]{"Josh"},
(rs, rowNum) -> new Customer(rs.getLong("id"), rs.getString("first_name"), rs.getString("last_name"))
).forEach(customer -> log.info(customer.toString()));
diff --git a/src/main/java/hello/controller/HelloController.java b/src/main/java/hello/controller/HelloController.java
index f3602fa..051bd17 100644
--- a/src/main/java/hello/controller/HelloController.java
+++ b/src/main/java/hello/controller/HelloController.java
@@ -2,100 +2,89 @@
import hello.declaration.TimeClient;
import hello.model.SimpleTimeClient;
-import hello.model.Topic;
import hello.service.TopicService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.web.bind.annotation.RestController;
import org.springframework.web.bind.annotation.RequestMapping;
import java.time.LocalDate;
-import java.time.LocalDateTime;
-import java.time.LocalTime;
import java.time.ZoneId;
-import java.time.chrono.ChronoPeriod;
import java.time.temporal.ChronoUnit;
-import java.util.List;
-import java.util.regex.Pattern;
-import java.util.stream.Collector;
-import java.util.stream.Collectors;
@RestController
public class HelloController {
-
- String joinTemplate = "Joining All String ID's with JOIN method: ";
- String makeDistinctAndSortCharactersTemplate = "-------------Get all ID characters, select distict and sort with ID= ";
- String splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoinTemplate = "-------------Split All Id With Colon," +
- "Select ID With \"Java\" Keyword," +
- " Then Sort Then Join ";
- String findIdHavingCharacterTemplate = "-------------Return All ID having character \'g\' in it: ";
- String findAllFilesInPathAndSortTemplate = "---------Find all files in path and sort: ";
- String findParticularFileInPathAndSortTemplate = "----------Find File in present directory which strats with \"grad\",provided maximum depth=25 and sort : ";
- String findParticularFileInPathAndSortWithWalkFunctionTemplate = "----------Find File in present directory which strats with \"grad\",provided maximum depth=25 and sort : with walk function";
- String readFileWithStreamFunctionTemplate = "---------Read \"temp.txt\" file with stream functions, having \"print\" witin it: ";
-
-
@Autowired
private TopicService topicService;
/**
* Java 8 Date Time example
- *
- * @return
*/
@RequestMapping("/datetime")
public String index() {
- TimeClient myTimeClient = new SimpleTimeClient();
- LocalDateTime localDateTime = LocalDateTime.now();
- return "Greetings from Spring Boot! ----------------------" +
- "Datetime now is " + String.valueOf(myTimeClient.toString()) + "----------------------" +
- "Datetime tomorrow will be " + String.valueOf(myTimeClient.getLocalDateTime().plusDays(1)) + "----------------------" +
- "Datetime of previous month was " + String.valueOf(myTimeClient.getLocalDateTime().minus(1, ChronoUnit.MONTHS)) + "----------------------" +
- "Is this a leap year ? " + String.valueOf(LocalDate.now().isLeapYear()) + "----------------------" +
- "Default system zone id " + String.valueOf(ZoneId.systemDefault()) + "-------------------" +
- "Time in California: " + myTimeClient.getZonedDateTime("Canada/Central").toString();
-
+ var myTimeClient = new SimpleTimeClient();
+ return """
+ Greetings from Spring Boot! ----------------------\
+ Datetime now is %s----------------------\
+ Datetime tomorrow will be %s----------------------\
+ Datetime of previous month was %s----------------------\
+ Is this a leap year ? %s----------------------\
+ Default system zone id %s-------------------\
+ Time in California: %s""".formatted(
+ myTimeClient,
+ myTimeClient.getLocalDateTime().plusDays(1),
+ myTimeClient.getLocalDateTime().minus(1, ChronoUnit.MONTHS),
+ LocalDate.now().isLeapYear(),
+ ZoneId.systemDefault(),
+ myTimeClient.getZonedDateTime("Canada/Central"));
}
/**
* String Operations in Java 8
- *
- * @return
*/
@RequestMapping("/topic/string/operation")
public String showStringOperation() {
-
- String join = topicService.returnAllTopicIDWithStringSlicing();
- String makeDistinctAndSortCharacters = topicService.makeDistinctAndSortCharacters(join);
- String splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin = topicService
+ var join = topicService.returnAllTopicIDWithStringSlicing();
+ var makeDistinctAndSortCharacters = topicService.makeDistinctAndSortCharacters(join);
+ var splitResult = topicService
.splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin(join);
- String findIdHavingCharacter = topicService.findIdHavingCharacter();
-
- return joinTemplate + join
- + makeDistinctAndSortCharactersTemplate + makeDistinctAndSortCharacters
- + splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoinTemplate + splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin
- + findIdHavingCharacterTemplate + findIdHavingCharacter;
-
+ var findIdHavingCharacter = topicService.findIdHavingCharacter();
+
+ return """
+ Joining All String ID's with JOIN method: %s\
+ -------------Get all ID characters, select distict and sort with ID= %s\
+ -------------Split All Id With Colon,\
+ Select ID With "Java" Keyword,\
+ Then Sort Then Join %s\
+ -------------Return All ID having character 'g' in it: %s""".formatted(
+ join,
+ makeDistinctAndSortCharacters,
+ splitResult,
+ findIdHavingCharacter);
}
/**
* File Operation in Java 8
- * @return
*/
@RequestMapping("/topic/file/operation")
public String showFileOperation() {
- String findAllFilesInPathAndSort = topicService.findAllFilesInPathAndSort();
- String findParticularFileInPathAndSort = topicService.findParticularFileInPathAndSort();
- String findParticularFileInPathAndSortWithWalkFunction = topicService.findParticularFileInPathAndSortWithWalkFunction();
- String readFileWithStreamFunction = topicService.readFileWithStreamFunction();
- return findAllFilesInPathAndSortTemplate + findAllFilesInPathAndSort
- + findParticularFileInPathAndSortTemplate + findParticularFileInPathAndSort
- + findParticularFileInPathAndSortWithWalkFunctionTemplate + findParticularFileInPathAndSortWithWalkFunction
- + readFileWithStreamFunctionTemplate + readFileWithStreamFunction;
+ var findAllFilesInPathAndSort = topicService.findAllFilesInPathAndSort();
+ var findParticularFileInPathAndSort = topicService.findParticularFileInPathAndSort();
+ var findWithWalk = topicService.findParticularFileInPathAndSortWithWalkFunction();
+ var readFile = topicService.readFileWithStreamFunction();
+ return """
+ ---------Find all files in path and sort: %s\
+ ----------Find File in present directory which strats with "grad",\
+ provided maximum depth=25 and sort : %s\
+ ----------Find File in present directory which strats with "grad",\
+ provided maximum depth=25 and sort : with walk function%s\
+ ---------Read "temp.txt" file with stream functions, having "print" witin it: %s""".formatted(
+ findAllFilesInPathAndSort,
+ findParticularFileInPathAndSort,
+ findWithWalk,
+ readFile);
}
-
-
}
diff --git a/src/main/java/hello/service/TopicService.java b/src/main/java/hello/service/TopicService.java
index feffb92..e15c8ab 100644
--- a/src/main/java/hello/service/TopicService.java
+++ b/src/main/java/hello/service/TopicService.java
@@ -8,7 +8,6 @@
import java.io.IOException;
import java.nio.file.Files;
import java.nio.file.Path;
-import java.nio.file.Paths;
import java.util.*;
import java.util.regex.Pattern;
import java.util.stream.Collectors;
@@ -19,7 +18,7 @@
public class TopicService {
- private List topics = new ArrayList<>(Arrays.asList(
+ private final List topics = new ArrayList<>(List.of(
new Topic("spring", "Spring Framework", "Spring Framework Description"),
new Topic("java", "Core Java", "Java Description"),
new Topic("javascript", "javascript Framework", "javascript Framework Description")
@@ -30,13 +29,13 @@ public List getAllTopics() {
}
/**
- * Strean Example
- *
- * @param id
- * @return
+ * Stream Example
*/
public Topic getTopicWithId(String id) {
- return topics.stream().filter(topic -> topic.getId().equals(id)).findFirst().get();
+ return topics.stream()
+ .filter(topic -> topic.getId().equals(id))
+ .findFirst()
+ .orElse(null);
}
public void addTopic(Topic topic) {
@@ -45,29 +44,25 @@ public void addTopic(Topic topic) {
/**
* IntStream examples
- *
- * @param id
- * @param topic
*/
public void updateTopic(String id, Topic topic) {
- OptionalInt indexOfElement = IntStream.range(0, topics.size()).filter(index -> id.equals(topics.get(index).getId())).findFirst();
- if (indexOfElement.isPresent()) topics.set(indexOfElement.getAsInt(), topic);
+ var indexOfElement = IntStream.range(0, topics.size())
+ .filter(index -> id.equals(topics.get(index).getId()))
+ .findFirst();
+ if (indexOfElement.isPresent()) {
+ topics.set(indexOfElement.getAsInt(), topic);
+ }
}
/**
- * Lamda Expressions
- *
- * @param id
+ * Lambda Expressions
*/
public void deleteTopic(String id) {
topics.removeIf(topic -> topic.getId().equals(id));
}
/**
- * Calling fucntional Interface
- *
- * @param minLength
- * @return
+ * Calling functional Interface
*/
public List filterMinimumLengthForId(Integer minLength) {
return printTopicsWithPredicate(topics, topic -> topic.getId().length() > minLength);
@@ -76,13 +71,9 @@ public List filterMinimumLengthForId(Integer minLength) {
/**
* Functional Interface example With ForEach
- *
- * @param topicList
- * @param tester
- * @return
*/
private static List printTopicsWithPredicate(List topicList, CustomPredicate tester) {
- List resultTopic = new ArrayList<>();
+ var resultTopic = new ArrayList();
topicList.forEach(topic -> {
if (tester.test(topic)) resultTopic.add(topic);
});
@@ -92,8 +83,6 @@ private static List printTopicsWithPredicate(List topicList, Custo
/**
* Using Comparator to sort
- *
- * @return
*/
public List sortTopicsWithID() {
topics.sort(Comparator.comparing(Topic::getId));
@@ -103,20 +92,17 @@ public List sortTopicsWithID() {
/**
* Join List of Strings
- *
- * @return
*/
public String returnAllTopicIDWithStringSlicing() {
- List topicIds = topics.stream().map(topic -> topic.getId()).collect(Collectors.toList());
+ var topicIds = topics.stream()
+ .map(Topic::getId)
+ .collect(Collectors.toList());
return String.join(":", topicIds);
}
/**
* Use of MapToObject and distinct
- *
- * @param join
- * @return
*/
public String makeDistinctAndSortCharacters(String join) {
return join.chars().distinct()
@@ -128,9 +114,6 @@ public String makeDistinctAndSortCharacters(String join) {
/**
* Use of Pattern Class with stream
- *
- * @param join
- * @return
*/
public String splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin(String join) {
return Pattern.compile(":")
@@ -143,13 +126,12 @@ public String splitAllIdWithColonSelectIDWithJavaKeywordThenSortThenJoin(String
/**
* Apply Regex as Predicate with Stream
- * @return
*/
public String findIdHavingCharacter() {
- Pattern pattern = Pattern.compile(".*g.*");
- Object[] topicIdObjectList = topics.stream().map(topic -> topic.getId()).collect(Collectors.toList()).toArray();
-
- String[] topicIdList = Arrays.stream(topicIdObjectList).toArray(String[]::new);
+ var pattern = Pattern.compile(".*g.*");
+ var topicIdList = topics.stream()
+ .map(Topic::getId)
+ .toArray(String[]::new);
return Stream.of(topicIdList)
.filter(pattern.asPredicate())
@@ -162,17 +144,14 @@ public String findIdHavingCharacter() {
* NIO Java API
* Use Streams with files
* Try with resource, "Autoclose"
- *
- * @return
*/
public String findAllFilesInPathAndSort() {
- try (Stream stream = Files.list(Paths.get(""))) {
- String joined = stream
+ try (var stream = Files.list(Path.of(""))) {
+ return stream
.map(String::valueOf)
.filter(path -> !path.startsWith("."))
.sorted()
.collect(Collectors.joining("; "));
- return joined;
} catch (IOException e) {
return " Error in IO";
}
@@ -180,18 +159,16 @@ public String findAllFilesInPathAndSort() {
/**
* Using File.find function to find file
- * @return
*/
public String findParticularFileInPathAndSort() {
- Path start = Paths.get("");
- int maxDepth = 25;
- try (Stream stream = Files.find(start, maxDepth, (path, attr) ->
+ var start = Path.of("");
+ var maxDepth = 25;
+ try (var stream = Files.find(start, maxDepth, (path, attr) ->
String.valueOf(path).startsWith("grad"))) {
- String joined = stream
+ return stream
.sorted()
.map(String::valueOf)
.collect(Collectors.joining("; "));
- return joined;
} catch (IOException e) {
return " IO exception ";
}
@@ -200,18 +177,16 @@ public String findParticularFileInPathAndSort() {
/**
* Using Files.Walk Function to find File
- * @return
*/
public String findParticularFileInPathAndSortWithWalkFunction() {
- Path start = Paths.get("");
- int maxDepth = 5;
- try (Stream stream = Files.walk(start, maxDepth)) {
- String joined = stream
+ var start = Path.of("");
+ var maxDepth = 5;
+ try (var stream = Files.walk(start, maxDepth)) {
+ return stream
.map(String::valueOf)
.filter(path -> path.startsWith("grad"))
.sorted()
.collect(Collectors.joining("; "));
- return joined;
} catch (IOException e) {
return " IO exception ";
}
@@ -220,18 +195,15 @@ public String findParticularFileInPathAndSortWithWalkFunction() {
/**
* Use BufferedReader with Stream functions
- * @return
*/
public String readFileWithStreamFunction() {
- Path path = Paths.get("temp.txt");
- System.out.println();
- try (BufferedReader reader = Files.newBufferedReader(path)) {
- String lines = reader
+ var path = Path.of("temp.txt");
+ try (var reader = Files.newBufferedReader(path)) {
+ return reader
.lines()
- .filter(line->line.contains("print"))
- .map(line->line.substring("print".length()))
+ .filter(line -> line.contains("print"))
+ .map(line -> line.substring("print".length()))
.collect(Collectors.joining(","));
- return lines;
} catch (IOException e) {
return " IO exception ";
}