Download to read offline
![?
for (i = 0; i < m; i++) {
free(a[i])
;
}
free(a);
// Trick Question ! Nothing :)
C Java](https://image.slidesharecdn.com/futureofjava3-220909161536-379f0efb/85/The-Future-of-JVM-Languages-16-320.jpg)
![public class ObjectExample {
private int value;
private String name;
public ObjectExample(int value, String name) {
this.value = value;
this.name = name;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public int getValue() {
return value;
}
public void setValue(int value) {
this.value = value;
}
public static void main(String[] args) {
ObjectExample object = new ObjectExample(1,"Awesome");
System.out.println("Name " + object.getName() + " Value " + object.getValue());
}
}
Java -> Groovy Objects
class ObjectExample {
int value
String name
}
object = new ObjectExample(value:1,name:"Awesome")
println "Name $object.name Value $object.value"
implicit Getters/Setters
semi colons optional
parentheses optional
interpolated Strings
named properties in Constructor
static void main not needed
variable type optional
default static imports](https://image.slidesharecdn.com/futureofjava3-220909161536-379f0efb/85/The-Future-of-JVM-Languages-23-320.jpg)
![import java.util.Arrays;
import java.util.HashMap;
import java.util.List;
import java.util.Map;
public class Main {
public static void main(String[] args) {
List<Integer> someItems = Arrays.asList(new Integer[]{1, 2, 3, 4});
for (Integer item : someItems) {
System.out.println(item);
}
Map<String, String> someMapping = new HashMap<>();
someMapping.put("ST", "started");
someMapping.put("IP", "in progress");
someMapping.put("DN", "done");
for (Map.Entry<String, String> entry : someMapping.entrySet()) {
String key = entry.getKey();
String value = entry.getValue();
System.out.println(key + " => " + value);
}
}
}
Java -> Groovy Collections
def someItems = [1, 2, 3, 4]
someItems.each {
println it
}
def someMapping = ["ST": "started", "IP": "in progress", "DN": "done"]
someMapping.each { key, val ->
println "$key => $val"
}
collection literals
default collection imports
closure parameter def optional (it)](https://image.slidesharecdn.com/futureofjava3-220909161536-379f0efb/85/The-Future-of-JVM-Languages-26-320.jpg)
![import java.sql.*;
import java.util.ArrayList;
import java.util.List;
public class JavaSqlExample {
static class Book {
public String name;
public int price;
public Book(String name, int price) {
this.name = name;
this.price = price;
}
}
public static void main(String[] args) throws SQLException{
List<Book> books = new ArrayList<>();
try (Connection con = DriverManager.getConnection("jdbc:h2:mem:")) {
con.prepareStatement("CREATE TABLE books " +
"AS SELECT 'Animal Farm' AS name, 123 AS price").execute();
try (ResultSet rs = con.prepareStatement("SELECT * FROM books").executeQuery()) {
while (rs.next()) {
books.add(new Book(rs.getString("name"), rs.getInt("price")));
}
}
}
books.forEach((book) -> System.out.println("Book " + book.name + " Price - " + book.price));
}
}
Java -> Groovy SQL
def sql = Sql.newInstance "jdbc:h2:mem:"
sql.execute """
CREATE TABLE books
AS SELECT 'Animal Farm' AS name, 123 AS price
"""
sql.rows "SELECT * FROM books" each {
println "Book - $it.name , Price - $it.price"
}
sql.close()
multiline strings
dynamic types
simpli
fi
ed SQL](https://image.slidesharecdn.com/futureofjava3-220909161536-379f0efb/85/The-Future-of-JVM-Languages-27-320.jpg)
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- 44. ▸Steep Learning Curve ▸CompatibilityIssues ▸Lackluster IDE Support ▸Negative Market Trend ▸Including Companies moving back to Java (including Twitter) ▸Opinion -> Strong Pass * SCALA Rare niches aside (Big Data)
- 45. GROOVY ▸Easy Learning Curve ▸StrongIndustry and IDE Support (JetBrains/Google) ▸Dynamic Typing (a double edged sword) ▸Slowed Adoption ▸Opinion -> Consider (for build scripts and testing) ▸Prefer Gradle over Maven :)
- 46. ▸Strong Industry andIDE Support ▸Modern Java 19+ features have still no caught up with alternatives ▸Opinion -> Consider JAVA 19+ (OR 8)
- 47. ▸Easy Learning Curve ▸StrongIndustry and IDE Support (JetBrains/Google) ▸True Null Safety ▸Gradle Scripts can be written in Kotlin ▸Opinion -> Strong Consider (especially for Android) KOTLIN
- 48.
- 49.
- 50. ▸Abstraction as aCore Productivity Accelerator ▸Diminishing returns with Higher Level Languages ▸Stronger returns are often elsewhere (frameworks, cloud, etc) ▸Consider Kotlin / Groovy (testing / building) / Scala as JVM alternatives ▸Java isn’t going away TAKEAWAYS
- 51.