Simplify json processing example (#2340)

Author: acoburn

solid/src/test/java/com/inrupt/client/solid/SolidClientTest.java

@@ -132,15 +132,18 @@ void testCustomHeaders() throws Exception {
     @Test
     void testJsonResource() {
         final URI uri = URI.create(config.get("solid_resource_uri") + "/transaction");
-        client.read(uri, Transaction.class).thenAccept(transaction -> {
-            try (final Transaction t = transaction) {
-                assertEquals("sample description", t.getDescription());
-                assertEquals(TransactionType.CREDIT, t.getType());
-                final var err = assertThrows(CompletionException.class, client.update(t).toCompletableFuture()::join);
+        client.read(uri, TransactionResource.class).thenAccept(res -> {
+            try (final TransactionResource tr = res) {
+                final var transaction = tr.getTransaction();
+                assertEquals("sample description", transaction.description());
+                assertEquals(TransactionResource.TransactionType.CREDIT, transaction.type());
+                final var err = assertThrows(CompletionException.class, client.update(tr).toCompletableFuture()::join);
                 assertTrue(err.getCause() instanceof ForbiddenException);
-                t.setType(TransactionType.DEBIT);
-                t.setDescription("different description");
-                assertDoesNotThrow(client.update(t).toCompletableFuture()::join);
+                tr.setTransaction(TransactionResource.Transaction.newBuilder(transaction)
+                    .type(TransactionResource.TransactionType.DEBIT)
+                    .description("different description")
+                    .build());
+                assertDoesNotThrow(client.update(tr).toCompletableFuture()::join);
             }
         }).toCompletableFuture().join();
     }

solid/src/test/java/com/inrupt/client/solid/Transaction.java

@@ -0,0 +1,132 @@
+/*
+ * Copyright Inrupt Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal in
+ * the Software without restriction, including without limitation the rights to use,
+ * copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the
+ * Software, and to permit persons to whom the Software is furnished to do so,
+ * subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED,
+ * INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A
+ * PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT
+ * HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+ * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+package com.inrupt.client.solid;
+
+import com.inrupt.client.spi.JsonService;
+import com.inrupt.client.spi.ServiceProvider;
+
+import java.io.ByteArrayInputStream;
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.UncheckedIOException;
+import java.net.URI;
+import java.time.Instant;
+import java.util.Objects;
+
+class TransactionResource extends SolidNonRDFSource {
+
+    private final JsonService jsonService;
+
+    private Transaction transaction;
+
+    public TransactionResource(final URI identifier, final String contentType, final InputStream entity) {
+        super(identifier, contentType, entity);
+
+        this.jsonService = ServiceProvider.getJsonService();
+        try {
+            this.transaction = jsonService.fromJson(super.getEntity(), Transaction.class);
+        } catch (IOException ex) {
+            throw new UncheckedIOException("Unable to parse Transaction data", ex);
+        }
+    }
+
+    public Transaction getTransaction() {
+        return transaction;
+    }
+
+    public void setTransaction(final Transaction transaction) {
+        this.transaction = Objects.requireNonNull(transaction, "transaction may not be null!");
+    }
+
+    @Override
+    public InputStream getEntity() throws IOException {
+        try (final ByteArrayOutputStream output = new ByteArrayOutputStream()) {
+            jsonService.toJson(transaction, output);
+            return new ByteArrayInputStream(output.toByteArray());
+        }
+    }
+
+    record Transaction(String id, String description, Instant date, double amount, TransactionType type,
+            String category) {
+        static class Builder {
+            private String transactionId;
+            private String transactionDescription;
+            private Instant transactionDate;
+            private double transactionAmount;
+            private TransactionType transactionType;
+            private String transactionCategory;
+
+            public Builder id(final String id) {
+                this.transactionId = id;
+                return this;
+            }
+
+            public Builder description(final String description) {
+                this.transactionDescription = description;
+                return this;
+            }
+
+            public Builder date(final Instant date) {
+                this.transactionDate = date;
+                return this;
+            }
+
+            public Builder amount(final double amount) {
+                this.transactionAmount = amount;
+                return this;
+            }
+
+            public Builder type(final TransactionType type) {
+                this.transactionType = type;
+                return this;
+            }
+
+            public Builder category(final String category) {
+                this.transactionCategory = category;
+                return this;
+            }
+
+            public Transaction build() {
+                return new Transaction(this.transactionId, this.transactionDescription, this.transactionDate,
+                        this.transactionAmount, this.transactionType, this.transactionCategory);
+            }
+        }
+
+        static Builder newBuilder() {
+            return new Builder();
+        }
+
+        static Builder newBuilder(final Transaction transaction) {
+            return new Builder()
+                .id(transaction.id())
+                .description(transaction.description())
+                .date(transaction.date())
+                .amount(transaction.amount())
+                .type(transaction.type())
+                .category(transaction.category());
+        }
+    }
+
+    enum TransactionType {
+        CREDIT, DEBIT
+    }
+}