Remove boilerplate code for parameter null checks

acme4j-client/src/main/java/org/shredzone/acme4j/AcmeResource.java

@@ -13,6 +13,8 @@
  */
 package org.shredzone.acme4j;
 
+import static org.shredzone.acme4j.util.AcmeUtils.assertNotNull;
+
 import java.io.Serializable;
 import java.net.URI;
 
@@ -50,10 +52,7 @@ public abstract class AcmeResource implements Serializable {
      * Sets a new {@link Session}.
      */
     protected void setSession(Session session) {
-        if (session == null) {
+        assertNotNull(session, "session");
-            throw new NullPointerException("session must not be null");
-        }
-
         this.session = session;
     }
 
@@ -61,10 +60,7 @@ public abstract class AcmeResource implements Serializable {
      * Sets the resource's location.
      */
     protected void setLocation(URI location) {
-        if (location == null) {
+        assertNotNull(location, "location");
-            throw new NullPointerException("location must not be null");
-        }
-
         this.location = location;
     }
 

acme4j-client/src/main/java/org/shredzone/acme4j/Registration.java

@@ -36,6 +36,7 @@ import org.shredzone.acme4j.connector.ResourceIterator;
 import org.shredzone.acme4j.exception.AcmeException;
 import org.shredzone.acme4j.exception.AcmeProtocolException;
 import org.shredzone.acme4j.exception.AcmeRetryAfterException;
+import org.shredzone.acme4j.util.AcmeUtils;
 import org.shredzone.acme4j.util.ClaimBuilder;
 import org.shredzone.acme4j.util.DomainUtils;
 import org.shredzone.acme4j.util.SignatureUtils;
@@ -176,8 +177,9 @@ public class Registration extends AcmeResource {
      * @return {@link Authorization} object for this domain
      */
     public Authorization authorizeDomain(String domain) throws AcmeException {
-        if (domain == null || domain.isEmpty()) {
+        AcmeUtils.assertNotNull(domain, "domain");
-            throw new NullPointerException("domain must not be empty or null");
+        if (domain.isEmpty()) {
+            throw new IllegalArgumentException("domain must not be empty");
         }
 
         LOG.debug("authorizeDomain {}", domain);
@@ -229,9 +231,7 @@ public class Registration extends AcmeResource {
      */
     public Certificate requestCertificate(byte[] csr, Date notBefore, Date notAfter)
                 throws AcmeException {
-        if (csr == null) {
+        AcmeUtils.assertNotNull(csr, "csr");
-            throw new NullPointerException("csr must not be null");
-        }
 
         LOG.debug("requestCertificate");
         try (Connection conn = getSession().provider().connect()) {
@@ -269,9 +269,7 @@ public class Registration extends AcmeResource {
      *            new {@link KeyPair} to be used for identifying this account
      */
     public void changeKey(KeyPair newKeyPair) throws AcmeException {
-        if (newKeyPair == null) {
+        AcmeUtils.assertNotNull(newKeyPair, "newKeyPair");
-            throw new NullPointerException("newKeyPair must not be null");
-        }
         if (Arrays.equals(getSession().getKeyPair().getPrivate().getEncoded(),
                         newKeyPair.getPrivate().getEncoded())) {
             throw new IllegalArgumentException("newKeyPair must actually be a new key pair");

acme4j-client/src/main/java/org/shredzone/acme4j/Session.java

@@ -30,6 +30,7 @@ import org.shredzone.acme4j.connector.Resource;
 import org.shredzone.acme4j.exception.AcmeException;
 import org.shredzone.acme4j.exception.AcmeProtocolException;
 import org.shredzone.acme4j.provider.AcmeProvider;
+import org.shredzone.acme4j.util.AcmeUtils;
 
 /**
  * A session stores the ACME server URI and the account's key pair. It also tracks
@@ -71,13 +72,8 @@ public class Session {
      *            {@link KeyPair} of the ACME account
      */
     public Session(URI serverUri, KeyPair keyPair) {
-        if (serverUri == null) {
+        AcmeUtils.assertNotNull(serverUri, "serverUri");
-            throw new NullPointerException("serverUri must not be null");
+        AcmeUtils.assertNotNull(keyPair, "keyPair");
-        }
-
-        if (keyPair == null) {
-            throw new NullPointerException("keypair must not be null");
-        }
 
         this.serverUri = serverUri;
         this.keyPair = keyPair;
@@ -170,9 +166,7 @@ public class Session {
      * @return {@link Challenge} instance
      */
     public Challenge createChallenge(Map<String, Object> data) {
-        if (data == null) {
+        AcmeUtils.assertNotNull(data, "data");
-            throw new NullPointerException("data must not be null");
-        }
 
         String type = (String) data.get("type");
         if (type == null || type.isEmpty()) {
@@ -200,9 +194,7 @@ public class Session {
      * @return {@link URI}, or {@code null} if the server does not offer that resource
      */
     public URI resourceUri(Resource resource) throws AcmeException {
-        if (resource == null) {
+        AcmeUtils.assertNotNull(resource, "resource");
-            throw new NullPointerException("resource must not be null");
-        }
         readDirectory();
         return resourceMap.get(resource);
     }

acme4j-client/src/main/java/org/shredzone/acme4j/challenge/Challenge.java

@@ -31,6 +31,7 @@ import org.shredzone.acme4j.connector.Connection;
 import org.shredzone.acme4j.exception.AcmeException;
 import org.shredzone.acme4j.exception.AcmeProtocolException;
 import org.shredzone.acme4j.exception.AcmeRetryAfterException;
+import org.shredzone.acme4j.util.AcmeUtils;
 import org.shredzone.acme4j.util.ClaimBuilder;
 import org.shredzone.acme4j.util.TimestampParser;
 import org.slf4j.Logger;
@@ -67,12 +68,8 @@ public class Challenge extends AcmeResource {
      */
     @SuppressWarnings("unchecked")
     public static <T extends Challenge> T bind(Session session, URI location) throws AcmeException {
-        if (session == null) {
+        AcmeUtils.assertNotNull(session, "session");
-            throw new NullPointerException("session must not be null");
+        AcmeUtils.assertNotNull(location, "location");
-        }
-        if (location == null) {
-            throw new NullPointerException("location must not be null");
-        }
 
         LOG.debug("bind");
         try (Connection conn = session.provider().connect()) {

acme4j-client/src/main/java/org/shredzone/acme4j/connector/DefaultConnection.java

@@ -49,6 +49,7 @@ import org.shredzone.acme4j.exception.AcmeProtocolException;
 import org.shredzone.acme4j.exception.AcmeRateLimitExceededException;
 import org.shredzone.acme4j.exception.AcmeServerException;
 import org.shredzone.acme4j.exception.AcmeUnauthorizedException;
+import org.shredzone.acme4j.util.AcmeUtils;
 import org.shredzone.acme4j.util.ClaimBuilder;
 import org.shredzone.acme4j.util.SignatureUtils;
 import org.slf4j.Logger;
@@ -71,21 +72,14 @@ public class DefaultConnection implements Connection {
     protected HttpURLConnection conn;
 
     public DefaultConnection(HttpConnector httpConnector) {
-        if (httpConnector == null) {
+        AcmeUtils.assertNotNull(httpConnector, "httpConnector");
-            throw new NullPointerException("httpConnector must not be null");
-        }
-
         this.httpConnector = httpConnector;
     }
 
     @Override
     public void sendRequest(URI uri, Session session) throws AcmeException {
-        if (uri == null) {
+        AcmeUtils.assertNotNull(uri, "uri");
-            throw new NullPointerException("uri must not be null");
+        AcmeUtils.assertNotNull(session, "session");
-        }
-        if (session == null) {
-            throw new NullPointerException("session must not be null");
-        }
         assertConnectionIsClosed();
 
         LOG.debug("GET {}", uri);
@@ -107,15 +101,9 @@ public class DefaultConnection implements Connection {
 
     @Override
     public void sendSignedRequest(URI uri, ClaimBuilder claims, Session session) throws AcmeException {
-        if (uri == null) {
+        AcmeUtils.assertNotNull(uri, "uri");
-            throw new NullPointerException("uri must not be null");
+        AcmeUtils.assertNotNull(claims, "claims");
-        }
+        AcmeUtils.assertNotNull(session, "session");
-        if (claims == null) {
-            throw new NullPointerException("claims must not be null");
-        }
-        if (session == null) {
-            throw new NullPointerException("session must not be null");
-        }
         assertConnectionIsClosed();
 
         try {

acme4j-client/src/main/java/org/shredzone/acme4j/exception/AcmeServerException.java

@@ -14,6 +14,7 @@
 package org.shredzone.acme4j.exception;
 
 import org.shredzone.acme4j.connector.DefaultConnection;
+import org.shredzone.acme4j.util.AcmeUtils;
 
 /**
  * An exception that is thrown when the ACME server returned an error. It contains
@@ -35,9 +36,7 @@ public class AcmeServerException extends AcmeException {
      */
     public AcmeServerException(String type, String detail) {
         super(detail);
-        if (type == null) {
+        AcmeUtils.assertNotNull(type, "type");
-            throw new IllegalArgumentException("Error type must not be null");
-        }
         this.type = type;
     }
 

acme4j-client/src/main/java/org/shredzone/acme4j/provider/AbstractAcmeProvider.java

@@ -27,6 +27,7 @@ import org.shredzone.acme4j.connector.Connection;
 import org.shredzone.acme4j.connector.DefaultConnection;
 import org.shredzone.acme4j.connector.HttpConnector;
 import org.shredzone.acme4j.exception.AcmeException;
+import org.shredzone.acme4j.util.AcmeUtils;
 
 /**
  * Abstract implementation of {@link AcmeProvider}. It consists of a challenge
@@ -58,11 +59,9 @@ public abstract class AbstractAcmeProvider implements AcmeProvider {
     @Override
     @SuppressWarnings("deprecation") // must still provide deprecated challenges
     public Challenge createChallenge(Session session, String type) {
-        if (session == null) {
+        AcmeUtils.assertNotNull(session, "session");
-            throw new NullPointerException("session must not be null");
+        AcmeUtils.assertNotNull(type, "type");
-        }
+        if (type.isEmpty()) {
-
-        if (type == null || type.isEmpty()) {
             throw new IllegalArgumentException("no type given");
         }
 

acme4j-client/src/main/java/org/shredzone/acme4j/util/AcmeUtils.java

@@ -78,4 +78,19 @@ public final class AcmeUtils {
         return Base64Url.encode(data);
     }
 
+    /**
+     * Asserts that the given value is not {@code null}. Otherwise a
+     * {@link NullPointerException} is thrown.
+     *
+     * @param value
+     *            Value to test
+     * @param name
+     *            Name of the parameter
+     */
+    public static void assertNotNull(Object value, String name) {
+        if (value == null) {
+            throw new NullPointerException(name + " must not be null");
+        }
+    }
+
 }

acme4j-client/src/main/java/org/shredzone/acme4j/util/ClaimBuilder.java

@@ -56,10 +56,7 @@ public class ClaimBuilder {
      * @return {@code this}
      */
     public ClaimBuilder put(String key, Object value) {
-        if (key == null) {
+        AcmeUtils.assertNotNull(key, "key");
-            throw new NullPointerException("key must not be null");
-        }
-
         data.put(key, value);
         return this;
     }
@@ -144,9 +141,7 @@ public class ClaimBuilder {
      * @return {@code this}
      */
     public ClaimBuilder putKey(String key, PublicKey publickey) {
-        if (publickey == null) {
+        AcmeUtils.assertNotNull(publickey, "publickey");
-            throw new NullPointerException("publickey must not be null");
-        }
 
         try {
             final PublicJsonWebKey jwk = PublicJsonWebKey.Factory.newPublicJwk(publickey);

acme4j-client/src/test/java/org/shredzone/acme4j/provider/AbstractAcmeProviderTest.java

@@ -165,7 +165,7 @@ public class AbstractAcmeProviderTest {
         try {
             provider.createChallenge(session, (String) null);
             fail("null was accepted");
-        } catch (IllegalArgumentException ex) {
+        } catch (NullPointerException ex) {
             // expected
         }
 

acme4j-client/src/test/java/org/shredzone/acme4j/util/AcmeUtilsTest.java

@@ -14,7 +14,7 @@
 package org.shredzone.acme4j.util;
 
 import static org.hamcrest.Matchers.is;
-import static org.junit.Assert.assertThat;
+import static org.junit.Assert.*;
 import static org.shredzone.acme4j.util.AcmeUtils.*;
 
 import javax.xml.bind.DatatypeConverter;
@@ -54,4 +54,19 @@ public class AcmeUtilsTest {
         assertThat(base64UrlEncode, is("w6uP8Tcg6K2QR905Rms8iXTlksL6OD1KOWBxTK7wxPI"));
     }
 
+    /**
+     * Test that {@code null} check works properly.
+     */
+    @Test
+    public void testAssertNotNull() {
+        AcmeUtils.assertNotNull(new Object(), "foo");
+
+        try {
+            AcmeUtils.assertNotNull(null, "bar");
+            fail("null was accepted");
+        } catch (NullPointerException ex) {
+            // expected
+        }
+    }
+
 }

acme4j-utils/src/main/java/org/shredzone/acme4j/util/CSRBuilder.java

@@ -145,12 +145,10 @@ public class CSRBuilder {
      *            {@link KeyPair} to sign the CSR with
      */
     public void sign(KeyPair keypair) throws IOException {
+        AcmeUtils.assertNotNull(keypair, "keypair");
         if (namelist.isEmpty()) {
             throw new IllegalStateException("No domain was set");
         }
-        if (keypair == null) {
-            throw new IllegalArgumentException("keypair must not be null");
-        }
 
         try {
             GeneralName[] gns = new GeneralName[namelist.size()];