property conversion

spring-boot/src/main/java/org/baeldung/properties/ConfigPropertiesDemoApplication.java

@@ -5,7 +5,7 @@ import org.springframework.boot.builder.SpringApplicationBuilder;
 import org.springframework.context.annotation.ComponentScan;
 
 @SpringBootApplication
-@ComponentScan(basePackageClasses = { ConfigProperties.class, JsonProperties.class, CustomJsonProperties.class })
+@ComponentScan(basePackageClasses = { ConfigProperties.class, JsonProperties.class, CustomJsonProperties.class, PropertyConversion.class, EmployeeConverter.class })
 public class ConfigPropertiesDemoApplication {
     public static void main(String[] args) {
         new SpringApplicationBuilder(ConfigPropertiesDemoApplication.class).initializers(new JsonPropertyContextInitializer())

spring-boot/src/main/java/org/baeldung/properties/Employee.java

@@ -0,0 +1,30 @@
+package org.baeldung.properties;
+
+public class Employee {
+
+    private String name;
+    private double salary;
+
+    public Employee(String name, double salary) {
+        super();
+        this.name = name;
+        this.salary = salary;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public double getSalary() {
+        return salary;
+    }
+
+    public void setSalary(double salary) {
+        this.salary = salary;
+    }
+
+}

spring-boot/src/main/java/org/baeldung/properties/EmployeeConverter.java

@@ -0,0 +1,16 @@
+package org.baeldung.properties;
+
+import org.springframework.boot.context.properties.ConfigurationPropertiesBinding;
+import org.springframework.core.convert.converter.Converter;
+import org.springframework.stereotype.Component;
+
+@Component
+@ConfigurationPropertiesBinding
+public class EmployeeConverter implements Converter<String, Employee> {
+
+    @Override
+    public Employee convert(String from) {
+        String[] data = from.split(",");
+        return new Employee(data[0], Double.parseDouble(data[1]));
+    }
+}

spring-boot/src/main/java/org/baeldung/properties/PropertyConversion.java

@@ -0,0 +1,92 @@
+package org.baeldung.properties;
+
+import java.time.Duration;
+import java.time.temporal.ChronoUnit;
+
+import org.springframework.boot.context.properties.ConfigurationProperties;
+import org.springframework.boot.convert.DataSizeUnit;
+import org.springframework.boot.convert.DurationUnit;
+import org.springframework.context.annotation.Configuration;
+import org.springframework.context.annotation.PropertySource;
+import org.springframework.util.unit.DataSize;
+import org.springframework.util.unit.DataUnit;
+
+@Configuration
+@PropertySource("classpath:conversion.properties")
+@ConfigurationProperties(prefix = "conversion")
+public class PropertyConversion {
+    private Duration timeInDefaultUnit;
+
+    private Duration timeInNano;
+
+    @DurationUnit(ChronoUnit.DAYS)
+    private Duration timeInDays;
+
+    private DataSize sizeInDefaultUnit;
+
+    private DataSize sizeInGB;
+
+    @DataSizeUnit(DataUnit.TERABYTES)
+    private DataSize sizeInTB;
+
+    private Employee employee;
+
+    // Getters and setters
+
+    public Duration getTimeInDefaultUnit() {
+        return timeInDefaultUnit;
+    }
+
+    public void setTimeInDefaultUnit(Duration timeInDefaultUnit) {
+        this.timeInDefaultUnit = timeInDefaultUnit;
+    }
+
+    public Duration getTimeInNano() {
+        return timeInNano;
+    }
+
+    public void setTimeInNano(Duration timeInNano) {
+        this.timeInNano = timeInNano;
+    }
+
+    public Duration getTimeInDays() {
+        return timeInDays;
+    }
+
+    public void setTimeInDays(Duration timeInDays) {
+        this.timeInDays = timeInDays;
+    }
+
+    public DataSize getSizeInDefaultUnit() {
+        return sizeInDefaultUnit;
+    }
+
+    public void setSizeInDefaultUnit(DataSize sizeInDefaultUnit) {
+        this.sizeInDefaultUnit = sizeInDefaultUnit;
+    }
+
+    public DataSize getSizeInGB() {
+        return sizeInGB;
+    }
+
+    public void setSizeInGB(DataSize sizeInGB) {
+        this.sizeInGB = sizeInGB;
+    }
+
+    public DataSize getSizeInTB() {
+        return sizeInTB;
+    }
+
+    public void setSizeInTB(DataSize sizeInTB) {
+        this.sizeInTB = sizeInTB;
+    }
+
+    public Employee getEmployee() {
+        return employee;
+    }
+
+    public void setEmployee(Employee employee) {
+        this.employee = employee;
+    }
+
+}

spring-boot/src/test/java/org/baeldung/properties/PropertiesConversionIntegrationTest.java

@@ -0,0 +1,43 @@
+package org.baeldung.properties;
+
+import static org.junit.jupiter.api.Assertions.assertEquals;
+
+import java.time.Duration;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Autowired;
+import org.springframework.boot.test.context.SpringBootTest;
+import org.springframework.test.context.TestPropertySource;
+import org.springframework.test.context.junit4.SpringRunner;
+import org.springframework.util.unit.DataSize;
+
+@RunWith(SpringRunner.class)
+@SpringBootTest(classes = ConfigPropertiesDemoApplication.class)
+@TestPropertySource("classpath:conversion.properties")
+public class PropertiesConversionIntegrationTest {
+
+    @Autowired
+    private PropertyConversion properties;
+
+    @Test
+    public void whenUseTimeUnitPropertyConversion_thenSuccess() throws Exception {
+        assertEquals(Duration.ofMillis(10), properties.getTimeInDefaultUnit());
+        assertEquals(Duration.ofNanos(9), properties.getTimeInNano());
+        assertEquals(Duration.ofDays(2), properties.getTimeInDays());
+    }
+
+    @Test
+    public void whenUseDataSizePropertyConversion_thenSuccess() throws Exception {
+        assertEquals(DataSize.ofBytes(300), properties.getSizeInDefaultUnit());
+        assertEquals(DataSize.ofGigabytes(2), properties.getSizeInGB());
+        assertEquals(DataSize.ofTerabytes(4), properties.getSizeInTB());        
+    }
+   
+    @Test
+    public void whenUseCustomPropertyConverter_thenSuccess() throws Exception {
+        assertEquals("john", properties.getEmployee().getName());
+        assertEquals(2000.0, properties.getEmployee().getSalary());
+    }
+    
+}

spring-boot/src/test/resources/conversion.properties

@@ -0,0 +1,11 @@
+###### time unit
+conversion.timeInDefaultUnit=10
+conversion.timeInNano=9ns
+conversion.timeInDays=2
+
+###### data size
+conversion.sizeInDefaultUnit=300
+conversion.sizeInGB=2GB
+conversion.sizeInTB=4
+
+conversion.employee=john,2000