[BAEL-5245] Lombok ToString annotation (#11870)

lombok-2/src/main/java/com/baeldung/lombok/tostring/Account.java

@@ -0,0 +1,56 @@
+package com.baeldung.lombok.tostring;
+
+import lombok.ToString;
+
+@ToString
+public class Account {
+
+    private String name;
+
+    // render this field before any others (the highest ranked)
+    @ToString.Include(rank = 1)
+    private String id;
+
+    @ToString.Exclude
+    private String accountNumber;
+
+    // automatically excluded
+    private String $ignored;
+
+    @ToString.Include
+    String description() {
+        return "Account description";
+    }
+
+    public String getAccountNumber() {
+        return accountNumber;
+    }
+
+    public void setAccountNumber(String accountNumber) {
+        this.accountNumber = accountNumber;
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public void setName(String name) {
+        this.name = name;
+    }
+
+    public String getId() {
+        return id;
+    }
+
+    public void setId(String id) {
+        this.id = id;
+    }
+
+    public String get$ignored() {
+        return $ignored;
+    }
+
+    public void set$ignored(String value) {
+        this.$ignored = value;
+    }
+}

lombok-2/src/main/java/com/baeldung/lombok/tostring/AccountType.java

@@ -0,0 +1,9 @@
+package com.baeldung.lombok.tostring;
+
+import lombok.ToString;
+
+@ToString
+public enum AccountType {
+    CHECKING,
+    SAVING
+}

lombok-2/src/main/java/com/baeldung/lombok/tostring/RewardAccount.java

@@ -0,0 +1,27 @@
+package com.baeldung.lombok.tostring;
+
+import lombok.ToString;
+
+@ToString
+public class RewardAccount extends Account {
+
+    private String rewardAccountId;
+
+    private Object[] relatedAccounts;
+
+    public String getRewardAccountId() {
+        return rewardAccountId;
+    }
+
+    public void setRewardAccountId(String rewardAccountId) {
+        this.rewardAccountId = rewardAccountId;
+    }
+
+    public Object[] getRelatedAccounts() {
+        return relatedAccounts;
+    }
+
+    public void setRelatedAccounts(Object[] relatedAccounts) {
+        this.relatedAccounts = relatedAccounts;
+    }
+}

lombok-2/src/main/java/com/baeldung/lombok/tostring/SavingAccount.java

@@ -0,0 +1,17 @@
+package com.baeldung.lombok.tostring;
+
+import lombok.ToString;
+
+@ToString(callSuper = true)
+public class SavingAccount extends Account {
+
+    private String savingAccountId;
+
+    public String getSavingAccountId() {
+        return savingAccountId;
+    }
+
+    public void setSavingAccountId(String savingAccountId) {
+        this.savingAccountId = savingAccountId;
+    }
+}

lombok-2/src/test/java/com/baeldung/lombok/tostring/ToStringUnitTest.java

@@ -0,0 +1,66 @@
+package com.baeldung.lombok.tostring;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+class ToStringUnitTest {
+
+    @Test
+    void whenPrintObject_thenOutputIsCorrect() {
+        Account account = new Account();
+        account.setId("12345");
+        account.setName("An account");
+        account.setAccountNumber("11111");      // should not be present in output
+        account.set$ignored("ignored value");   // should not be present in output
+
+        assertThat(account.toString())
+          .isEqualTo("Account(id=12345, name=An account, description=Account description)");
+    }
+
+    @Test
+    void whenPrintSubclassWithSuper_thenOutputIsCorrect() {
+        SavingAccount savingAccount = new SavingAccount();
+        savingAccount.setSavingAccountId("5678");
+        savingAccount.setId("12345");
+        savingAccount.setName("An account");
+
+        assertThat(savingAccount.toString())
+          .isEqualTo("SavingAccount(super=Account(id=12345, name=An account, description=Account description), savingAccountId=5678)");
+    }
+
+@Test
+void whenPrintArrays_thenOutputIsCorrect() {
+    RewardAccount account = new RewardAccount();
+    account.setRewardAccountId("12345");
+
+    // circular ref, just for demonstration
+    Object[] relatedAccounts = new Object[2];
+    relatedAccounts[0] = "54321";
+    relatedAccounts[1] = relatedAccounts;
+
+    account.setRelatedAccounts(relatedAccounts);
+
+    assertThat(account.toString())
+      .isEqualTo("RewardAccount(rewardAccountId=12345, relatedAccounts=[54321, [...]])");
+}
+
+    @Test
+    void whenPrintSubclassWithoutSuper_thenOutputIsCorrect() {
+        RewardAccount rewardAccount = new RewardAccount();
+        rewardAccount.setRewardAccountId("12345");
+
+        assertThat(rewardAccount.toString())
+          .isEqualTo("RewardAccount(rewardAccountId=12345, relatedAccounts=null)");
+    }
+
+    @Test
+    void whenPrintEnum_thenOutputIsCorrect() {
+        assertThat(AccountType.CHECKING.toString())
+          .isEqualTo("AccountType.CHECKING");
+
+        assertThat(AccountType.SAVING.toString())
+          .isEqualTo("AccountType.SAVING");
+    }
+
+}