new client api subproject

settings.gradle

@@ -1,6 +1,7 @@
 include 'z3950-asn1'
 include 'z3950-api'
 include 'z3950-common'
-include 'z3950-client'
+include 'z3950-client-api'
+include 'z3950-client-jdk'
 include 'z3950-client-netty'
 include 'z3950-sru'

z3950-client-api/build.gradle

@@ -0,0 +1,3 @@
+dependencies {
+    api project(':z3950-common')
+}

z3950-client-api/src/main/java/module-info.java

@@ -0,0 +1,4 @@
+module org.xbib.z3950lib.client.api {
+    exports org.xbib.z3950.client.api;
+    requires transitive org.xbib.z3950lib.common;
+}

z3950-client-api/src/main/java/org/xbib/z3950/client/api/Client.java

@@ -1,5 +1,8 @@
-package org.xbib.z3950.api;
+package org.xbib.z3950.client.api;
 
+import org.xbib.z3950.api.RecordListener;
+import org.xbib.z3950.api.ScanListener;
+import org.xbib.z3950.api.SearchListener;
 import java.io.Closeable;
 import java.io.IOException;
 import java.util.List;
@@ -7,8 +10,8 @@ import java.util.List;
 public interface Client extends Closeable {
 
     int searchCQL(String query, int offset, int length,
-                         SearchListener searchListener,
+                  SearchListener searchListener,
-                         RecordListener recordListener) throws IOException;
+                  RecordListener recordListener) throws IOException;
 
     int searchPQF(String query, int offset, int length,
                   SearchListener searchListener,
@@ -40,5 +43,4 @@ public interface Client extends Closeable {
     String getType();
 
     List<String> getDatabases();
-
 }

z3950-client-api/src/main/java/org/xbib/z3950/client/api/ClientProvider.java

@@ -1,4 +1,4 @@
-package org.xbib.z3950.api;
+package org.xbib.z3950.client.api;
 
 /**
  * Client provider.

z3950-client-jdk/build.gradle

@@ -1,4 +1,4 @@
 dependencies {
-    api project(':z3950-common')
+    api project(':z3950-client-api')
     testImplementation "org.xbib:bibliographic-character-sets:${project.property('xbib-bibliographic-character-sets.version')}"
-}
+}

z3950-client-jdk/src/main/java/module-info.java

@@ -0,0 +1,5 @@
+module org.xbib.z3950lib.client.jdk {
+    exports org.xbib.z3950.client.jdk;
+    requires transitive org.xbib.z3950lib.client.api;
+    requires java.logging;
+}

z3950-client-jdk/src/main/java/org/xbib/z3950/client/jdk/JDKZClient.java

@@ -1,4 +1,4 @@
-package org.xbib.z3950.client;
+package org.xbib.z3950.client.jdk;
 
 import org.xbib.asn1.io.InputStreamBERReader;
 import org.xbib.asn1.io.OutputStreamBERWriter;
@@ -7,14 +7,14 @@ import org.xbib.z3950.common.operations.InitOperation;
 import org.xbib.z3950.common.operations.PresentOperation;
 import org.xbib.z3950.common.operations.ScanOperation;
 import org.xbib.z3950.common.operations.SearchOperation;
-import org.xbib.z3950.api.Client;
+import org.xbib.z3950.client.api.Client;
 import org.xbib.z3950.api.InitListener;
 import org.xbib.z3950.api.RecordListener;
 import org.xbib.z3950.api.ScanListener;
 import org.xbib.z3950.api.SearchListener;
-
 import java.io.BufferedInputStream;
 import java.io.BufferedOutputStream;
+import java.io.Closeable;
 import java.io.IOException;
 import java.io.InputStream;
 import java.io.OutputStream;
@@ -32,9 +32,9 @@ import java.util.logging.Logger;
 /**
  * Default Z client.
  */
-public class DefaultClient implements Client {
+public class JDKZClient implements Client, Closeable {
 
-    private static final Logger logger = Logger.getLogger(DefaultClient.class.getName());
+    private static final Logger logger = Logger.getLogger(JDKZClient.class.getName());
 
     private final String host;
 
@@ -72,16 +72,16 @@ public class DefaultClient implements Client {
 
     private OutputStreamBERWriter berWriter;
 
-    private DefaultClient(String host, int port, String user, String pass, long timeout,
+    private JDKZClient(String host, int port, String user, String pass, long timeout,
-                          String preferredRecordSyntax,
+                       String preferredRecordSyntax,
-                          String resultSetName,
+                       String resultSetName,
-                          String elementSetName,
+                       String elementSetName,
-                          String encoding,
+                       String encoding,
-                          String format,
+                       String format,
-                          String type,
+                       String type,
-                          List<String> databases,
+                       List<String> databases,
-                          Integer preferredMessageSize,
+                       Integer preferredMessageSize,
-                          InitListener initListener) {
+                       InitListener initListener) {
         this.host = host;
         this.port = port;
         this.user = user;
@@ -99,39 +99,6 @@ public class DefaultClient implements Client {
         this.lock = new ReentrantLock();
     }
 
-    @Override
-    public void close() {
-        if (isConnected()) {
-            try {
-                lock.lock();
-                try {
-                    sendClose(0);
-                } catch (IOException e) {
-                    logger.log(Level.WARNING, "while attempting to send close for close connection: " + e.getMessage(), e);
-                }
-                try {
-                    berReader.close();
-                } catch (IOException e) {
-                    logger.log(Level.WARNING, "error attempting to close src: " + e.getMessage(), e);
-                }
-                try {
-                    berWriter.close();
-                } catch (IOException e) {
-                    logger.log(Level.WARNING, "error attempting to close dest: " + e.getMessage(), e);
-                }
-                try {
-                    if (socket != null) {
-                        socket.close();
-                    }
-                } catch (IOException e) {
-                    logger.log(Level.WARNING, "error attempting to close socket: " + e.getMessage(), e);
-                }
-            } finally {
-                lock.unlock();
-            }
-        }
-    }
-
     @Override
     public int searchCQL(String query, int offset, int length,
                          SearchListener searchListener,
@@ -288,8 +255,66 @@ public class DefaultClient implements Client {
         return databases;
     }
 
-    private void connect() throws IOException {
+    public void connect() throws IOException {
+        try {
+            lock.lock();
+            Socket socket = new Socket();
+            socket.connect(new InetSocketAddress(host, port), (int) timeout);
+            socket.setSoTimeout((int) timeout * 1000);
+            this.socket = socket;
+            InputStream src = new BufferedInputStream(socket.getInputStream());
+            OutputStream dest = new BufferedOutputStream(socket.getOutputStream());
+            this.berReader = new InputStreamBERReader(src);
+            this.berWriter = new OutputStreamBERWriter(dest);
+            InitOperation initOperation = new InitOperation(berReader, berWriter, user, pass);
+            if (initOperation.execute(preferredMessageSize, initListener)) {
+                throw new IOException("could not initiate connection");
+            }
+            logger.log(Level.INFO, initOperation.getTargetInfo());
+        } finally {
+            lock.unlock();
+        }
+    }
 
+    public void disconnect() throws IOException {
+        try {
+            lock.lock();
+            try {
+                sendClose(0);
+            } catch (IOException e) {
+                logger.log(Level.WARNING, "while attempting to send close for close connection: " + e.getMessage(), e);
+            }
+            try {
+                berReader.close();
+            } catch (IOException e) {
+                logger.log(Level.WARNING, "error attempting to close src: " + e.getMessage(), e);
+            }
+            try {
+                berWriter.close();
+            } catch (IOException e) {
+                logger.log(Level.WARNING, "error attempting to close dest: " + e.getMessage(), e);
+            }
+            try {
+                if (socket != null) {
+                    socket.close();
+                }
+            } catch (IOException e) {
+                logger.log(Level.WARNING, "error attempting to close socket: " + e.getMessage(), e);
+            }
+        } finally {
+            lock.unlock();
+        }
+    }
+
+    @Override
+    public void close() throws IOException {
+        if (isConnected()) {
+            disconnect();
+        }
+    }
+
+    public static Builder builder() {
+        return new Builder();
     }
 
     private boolean isConnected() {
@@ -298,31 +323,10 @@ public class DefaultClient implements Client {
 
     private void ensureConnected() throws IOException {
         if (!isConnected()) {
-            try {
+           connect();
-                lock.lock();
-                Socket socket = new Socket();
-                socket.connect(new InetSocketAddress(host, port), (int) timeout);
-                socket.setSoTimeout((int) timeout * 1000);
-                this.socket = socket;
-                InputStream src = new BufferedInputStream(socket.getInputStream());
-                OutputStream dest = new BufferedOutputStream(socket.getOutputStream());
-                this.berReader = new InputStreamBERReader(src);
-                this.berWriter = new OutputStreamBERWriter(dest);
-                InitOperation initOperation = new InitOperation(berReader, berWriter, user, pass);
-                if (initOperation.execute(preferredMessageSize, initListener)) {
-                    throw new IOException("could not initiate connection");
-                }
-                logger.log(Level.INFO, initOperation.getTargetInfo());
-            } finally {
-                lock.unlock();
-            }
         }
     }
 
-    public static Builder builder() {
-        return new Builder();
-    }
-
     /**
      * Send a close request to the server.
      *
@@ -454,8 +458,8 @@ public class DefaultClient implements Client {
             return this;
         }
 
-        public DefaultClient build() {
+        public JDKZClient build() {
-            return new DefaultClient(host, port, user, pass, timeout,
+            return new JDKZClient(host, port, user, pass, timeout,
                     preferredRecordSyntax,
                     resultSetName,
                     elementSetName,

z3950-client-jdk/src/test/java/org/xbib/z3950/client/jdk/test/DefaultClientTest.java

@@ -1,7 +1,7 @@
-package org.xbib.z3950.client.test;
+package org.xbib.z3950.client.jdk.test;
 
 import org.junit.jupiter.api.Test;
-import org.xbib.z3950.client.DefaultClient;
+import org.xbib.z3950.client.jdk.JDKZClient;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -25,7 +25,7 @@ class DefaultClientTest {
             String query = "bib.identifierISSN = 00280836";
             int from = 1;
             int size = 10;
-            try (DefaultClient client = newZClient(serviceName)) {
+            try (JDKZClient client = newZClient(serviceName)) {
                 logger.log(Level.INFO, "executing CQL " + serviceName);
                 int count = client.searchCQL(query, from, size,
                         (status, total, returned, elapsedMillis) ->
@@ -44,7 +44,7 @@ class DefaultClientTest {
             String query = "@attr 1=8 \"00280836\"";
             int from = 1;
             int size = 10;
-            try (DefaultClient client = newZClient(serviceName)) {
+            try (JDKZClient client = newZClient(serviceName)) {
                 logger.log(Level.INFO, "executing PQF " + serviceName);
                 int count = client.searchPQF(query, from, size,
                         (status, total, returned, elapsedMillis) ->
@@ -57,7 +57,7 @@ class DefaultClientTest {
         }
     }
 
-    private DefaultClient newZClient(String name) throws IOException {
+    private JDKZClient newZClient(String name) throws IOException {
         return newZClient(getProperties(name));
     }
 
@@ -69,8 +69,8 @@ class DefaultClientTest {
         return properties;
     }
 
-    private static DefaultClient newZClient(Properties properties) {
+    private static JDKZClient newZClient(Properties properties) {
-        DefaultClient.Builder builder = DefaultClient.builder();
+        JDKZClient.Builder builder = JDKZClient.builder();
         if (properties.containsKey("host")) {
             builder.setHost(properties.getProperty("host"));
         }

z3950-client-jdk/src/test/java/org/xbib/z3950/client/jdk/test/GBVZClientTest.java

@@ -1,7 +1,7 @@
-package org.xbib.z3950.client.test;
+package org.xbib.z3950.client.jdk.test;
 
 import org.junit.jupiter.api.Test;
-import org.xbib.z3950.client.DefaultClient;
+import org.xbib.z3950.client.jdk.JDKZClient;
 
 import java.io.IOException;
 import java.io.InputStream;
@@ -25,7 +25,7 @@ class GBVZClientTest {
         String query = "@attr 1=4 linux";
         int from = 1;
         int size = 10;
-        try (DefaultClient client = newZClient("GBV")) {
+        try (JDKZClient client = newZClient("GBV")) {
             logger.log(Level.INFO, "executing PQF " + query);
             int count = client.searchPQF(query, from, size,
                     (status, total, returned, elapsedMillis) ->
@@ -43,7 +43,7 @@ class GBVZClientTest {
         String query = "bib.controlNumberZDB = 1413423-8";
         int from = 1;
         int size = 2;
-        try (DefaultClient client = newZClient(serviceName)) {
+        try (JDKZClient client = newZClient(serviceName)) {
             logger.log(Level.INFO, "executing CQL " + query);
             int count = client.searchCQL(query, from, size,
                     (status, total, returned, elapsedMillis) ->
@@ -57,7 +57,7 @@ class GBVZClientTest {
     }
 
 
-    private DefaultClient newZClient(String name) throws IOException {
+    private JDKZClient newZClient(String name) throws IOException {
         return newZClient(getProperties(name));
     }
 
@@ -69,8 +69,8 @@ class GBVZClientTest {
         return properties;
     }
 
-    private static DefaultClient newZClient(Properties properties) {
+    private static JDKZClient newZClient(Properties properties) {
-        DefaultClient.Builder builder = DefaultClient.builder();
+        JDKZClient.Builder builder = JDKZClient.builder();
         if (properties.containsKey("host")) {
             builder.setHost(properties.getProperty("host"));
         }

z3950-client-jdk/src/test/java/org/xbib/z3950/client/jdk/test/SearchTest.java

@@ -1,9 +1,9 @@
-package org.xbib.z3950.client.test;
+package org.xbib.z3950.client.jdk.test;
 
 import org.junit.jupiter.api.Test;
 import org.xbib.z3950.common.exceptions.MessageSizeTooSmallException;
 import org.xbib.z3950.common.exceptions.NoRecordsReturnedException;
-import org.xbib.z3950.client.DefaultClient;
+import org.xbib.z3950.client.jdk.JDKZClient;
 
 import java.util.Collections;
 import java.util.logging.Level;
@@ -27,7 +27,7 @@ class SearchTest {
         int from = 1;
         int length = 1;
         try {
-            DefaultClient client = DefaultClient.builder()
+            JDKZClient client = JDKZClient.builder()
                     .setHost(host)
                     .setPort(port)
                     .setDatabases(Collections.singletonList(database))

z3950-client-netty/build.gradle

@@ -1,5 +1,8 @@
 dependencies {
-    api project(':z3950-common')
+    api project(':z3950-client-api')
+    implementation "io.netty:netty-buffer:${project.property('netty.version')}"
+    implementation "io.netty:netty-common:${project.property('netty.version')}"
     implementation "io.netty:netty-handler:${project.property('netty.version')}"
     implementation "io.netty:netty-transport:${project.property('netty.version')}"
+    testImplementation "org.xbib:bibliographic-character-sets:${project.property('xbib-bibliographic-character-sets.version')}"
 }

z3950-client-netty/src/main/java/module-info.java

@@ -1,6 +1,9 @@
 module org.xbib.z3950lib.client.netty {
     exports org.xbib.z3950.client.netty;
-    requires transitive org.xbib.z3950lib.common;
+    requires transitive org.xbib.z3950lib.client.api;
+    requires io.netty.buffer;
+    requires io.netty.common;
     requires io.netty.handler;
     requires io.netty.transport;
+    requires java.logging;
 }

z3950-client-netty/src/main/java/org/xbib/z3950/client/netty/NettyZClient.java

@@ -13,12 +13,19 @@ import io.netty.channel.socket.SocketChannel;
 import io.netty.channel.socket.nio.NioSocketChannel;
 import io.netty.util.CharsetUtil;
 
+import org.xbib.z3950.api.RecordListener;
+import org.xbib.z3950.api.ScanListener;
+import org.xbib.z3950.api.SearchListener;
+import org.xbib.z3950.client.api.Client;
+import java.io.Closeable;
+import java.io.IOException;
 import java.net.InetSocketAddress;
+import java.util.List;
 
 /**
  *
  */
-public class NettyZClient {
+public class NettyZClient implements Client, Closeable {
 
     private final EventLoopGroup group;
     private final Bootstrap clientBootstrap;
@@ -46,6 +53,86 @@ public class NettyZClient {
         group.shutdownGracefully().sync();
     }
 
+    @Override
+    public void close() throws IOException {
+
+    }
+
+    @Override
+    public int searchCQL(String query, int offset, int length, SearchListener searchListener, RecordListener recordListener) throws IOException {
+        return 0;
+    }
+
+    @Override
+    public int searchPQF(String query, int offset, int length, SearchListener searchListener, RecordListener recordListener) throws IOException {
+        return 0;
+    }
+
+    @Override
+    public void scanPQF(String query, int nTerms, int step, int position, ScanListener scanListener) throws IOException {
+
+    }
+
+    @Override
+    public String getHost() {
+        return null;
+    }
+
+    @Override
+    public int getPort() {
+        return 0;
+    }
+
+    @Override
+    public String getUser() {
+        return null;
+    }
+
+    @Override
+    public String getPass() {
+        return null;
+    }
+
+    @Override
+    public long getTimeout() {
+        return 0;
+    }
+
+    @Override
+    public String getPreferredRecordSyntax() {
+        return null;
+    }
+
+    @Override
+    public String getResultSetName() {
+        return null;
+    }
+
+    @Override
+    public String getElementSetName() {
+        return null;
+    }
+
+    @Override
+    public String getEncoding() {
+        return null;
+    }
+
+    @Override
+    public String getFormat() {
+        return null;
+    }
+
+    @Override
+    public String getType() {
+        return null;
+    }
+
+    @Override
+    public List<String> getDatabases() {
+        return null;
+    }
+
     class Handler extends SimpleChannelInboundHandler<ByteBuf> {
 
         @Override

z3950-client/src/main/java/module-info.java

@@ -1,5 +0,0 @@
-module org.xbib.z3950lib.client {
-    exports org.xbib.z3950.client;
-    requires transitive org.xbib.z3950lib.common;
-    requires java.logging;
-}

z3950-common/src/main/java/org/xbib/z3950/common/cql/CQLRPNGenerator.java

@@ -32,6 +32,7 @@ import org.xbib.z3950.common.v3.Operator;
 import org.xbib.z3950.common.v3.RPNQuery;
 import org.xbib.z3950.common.v3.RPNStructure;
 import org.xbib.z3950.common.v3.RPNStructureRpnRpnOp;
+import java.util.Collection;
 import java.util.HashMap;
 import java.util.Map;
 import java.util.MissingResourceException;
@@ -70,6 +71,12 @@ public final class CQLRPNGenerator implements Visitor {
         this.result = new Stack<>();
     }
 
+    public CQLRPNGenerator(Collection<AttributeElement> attributeElements) {
+        this.attributeElements = new Stack<>();
+        this.attributeElements.addAll(attributeElements);
+        this.result = new Stack<>();
+    }
+
     public RPNQuery getQueryResult() {
         return rpnQuery;
     }
@@ -196,7 +203,8 @@ public final class CQLRPNGenerator implements Visitor {
             operand.attrTerm.term.c_general = new ASN1OctetString(node.getTerm().getValue());
         }
         operand.attrTerm.attributes = new AttributeList();
-        operand.attrTerm.attributes.value = attributeElements.toArray(new AttributeElement[0]);
+        operand.attrTerm.attributes.value = attributeElements.stream()
+                .filter(ae -> ae.attributeValue != null).toArray(AttributeElement[]::new);
         RPNStructure rpn = new RPNStructure();
         rpn.c_op = operand;
         result.push(rpn);
@@ -307,25 +315,17 @@ public final class CQLRPNGenerator implements Visitor {
 
     private ASN1OctetString transformTerm(Term term) {
         String v = term.getValue();
-        // let's derive attributes from the search term
+        // let's derive attributes from the search term syntax
 
         // relation attribute = 2
         int attributeType = 2;
         int attributeValue = 3; // equal = 3
-        AttributeElement ae = new AttributeElement();
+        push(attributeElements, createAttributeElement(attributeType, attributeValue));
-        ae.attributeType = new ASN1Integer(attributeType);
-        ae.attributeValue = new AttributeElementAttributeValue();
-        ae.attributeValue.numeric = new ASN1Integer(attributeValue);
-        attributeElements.push(ae);
 
         // position attribute = 3
-        attributeType = 3;
+        //attributeType = 3;
-        attributeValue = 3; // any position = 3
+        // attributeValue = 3; // any position = 3
-        ae = new AttributeElement();
+        //push(attributeElements, createAttributeElement(attributeType, attributeValue));
-        ae.attributeType = new ASN1Integer(attributeType);
-        ae.attributeValue = new AttributeElementAttributeValue();
-        ae.attributeValue.numeric = new ASN1Integer(attributeValue);
-        attributeElements.push(ae);
 
         // structure attribute = 4
         attributeType = 4;
@@ -334,11 +334,7 @@ public final class CQLRPNGenerator implements Visitor {
             attributeValue = 1; // phrase
             v = v.substring(1, v.length()-1);
         }
-        ae = new AttributeElement();
+        push(attributeElements, createAttributeElement(attributeType, attributeValue));
-        ae.attributeType = new ASN1Integer(attributeType);
-        ae.attributeValue = new AttributeElementAttributeValue();
-        ae.attributeValue.numeric = new ASN1Integer(attributeValue);
-        attributeElements.push(ae);
 
         // truncation attribute = 5
         attributeType = 5;
@@ -355,12 +351,27 @@ public final class CQLRPNGenerator implements Visitor {
             attributeValue = 2; // Left truncation = 2
             v = v.substring(1);
         }
-        ae = new AttributeElement();
+        push(attributeElements, createAttributeElement(attributeType, attributeValue));
-        ae.attributeType = new ASN1Integer(attributeType);
-        ae.attributeValue = new AttributeElementAttributeValue();
-        ae.attributeValue.numeric = new ASN1Integer(attributeValue);
-        attributeElements.push(ae);
-
         return new ASN1OctetString(v);
     }
+
+    private static void push(Stack<AttributeElement> stack, AttributeElement attributeElement) {
+        if (attributeElement != null) {
+            if (!stack.contains(attributeElement)) {
+                stack.push(attributeElement);
+            }
+        }
+    }
+
+    private static AttributeElement createAttributeElement(Integer attributeType, Integer attributeValue) {
+        if (attributeType != null && attributeValue != null) {
+            AttributeElement ae = new AttributeElement();
+            ae.attributeType = new ASN1Integer(attributeType);
+            ae.attributeValue = new AttributeElementAttributeValue();
+            ae.attributeValue.numeric = new ASN1Integer(attributeValue);
+            return ae;
+        } else {
+            return null;
+        }
+    }
 }

z3950-common/src/main/java/org/xbib/z3950/common/v3/AccessControlRequest.java

@@ -120,7 +120,7 @@ public final class AccessControlRequest extends ASN1Any {
         if (sOtherInfo != null) {
             numFields++;
         }
-        BEREncoding fields[] = new BEREncoding[numFields];
+        BEREncoding[] fields = new BEREncoding[numFields];
         int x = 0;
         if (sReferenceId != null) {
             fields[x++] = sReferenceId.berEncode();
@@ -149,11 +149,8 @@ public final class AccessControlRequest extends ASN1Any {
         }
         str.append("securityChallenge ");
         str.append(sSecurityChallenge);
-        outputted++;
         if (sOtherInfo != null) {
-            if (0 < outputted) {
+            str.append(", ");
-                str.append(", ");
-            }
             str.append("otherInfo ");
             str.append(sOtherInfo);
         }

z3950-common/src/main/java/org/xbib/z3950/common/v3/AccessControlRequestSecurityChallenge.java

@@ -82,7 +82,7 @@ public final class AccessControlRequestSecurityChallenge extends ASN1Any {
     @Override
     public BEREncoding berEncode() throws ASN1Exception {
         BEREncoding chosen = null;
-        BEREncoding enc[];
+        BEREncoding[] enc;
         if (cSimpleForm != null) {
             chosen = cSimpleForm.berEncode(BEREncoding.CONTEXT_SPECIFIC_TAG, 37);
         }

z3950-common/src/main/java/org/xbib/z3950/common/v3/AttributeElement.java

@@ -19,7 +19,7 @@ import org.xbib.asn1.BEREncoding;
  * }
  * </pre>
  */
-public final class AttributeElement extends ASN1Any {
+public final class AttributeElement extends ASN1Any implements Comparable<AttributeElement> {
 
     public AttributeSetId attributeSetId; // optional
 
@@ -125,7 +125,7 @@ public final class AttributeElement extends ASN1Any {
         if (attributeSetId != null) {
             numFields++;
         }
-        BEREncoding fields[] = new BEREncoding[numFields];
+        BEREncoding[] fields = new BEREncoding[numFields];
         int x = 0;
         if (attributeSetId != null) {
             fields[x++] = attributeSetId.berEncode(BEREncoding.CONTEXT_SPECIFIC_TAG, 1);
@@ -153,13 +153,15 @@ public final class AttributeElement extends ASN1Any {
         }
         str.append("attributeType ");
         str.append(attributeType);
-        outputted++;
+        str.append(", ");
-        if (0 < outputted) {
-            str.append(", ");
-        }
         str.append("attributeValue ");
         str.append(attributeValue);
         str.append("}");
         return str.toString();
     }
+
+    @Override
+    public int compareTo(AttributeElement o) {
+        return attributeType.toString().compareTo(o.attributeType.toString());
+    }
 }

z3950-common/src/test/java/org/xbib/z3950/common/cql/CQL2RPNTest.java

@@ -2,7 +2,11 @@ package org.xbib.z3950.common.cql;
 
 import static org.junit.jupiter.api.Assertions.assertEquals;
 import org.junit.jupiter.api.Test;
+import org.xbib.asn1.ASN1Integer;
 import org.xbib.cql.CQLParser;
+import org.xbib.z3950.common.v3.AttributeElement;
+import org.xbib.z3950.common.v3.AttributeElementAttributeValue;
+import java.util.Collections;
 
 class CQL2RPNTest {
 
@@ -14,7 +18,7 @@ class CQL2RPNTest {
         CQLRPNGenerator generator = new CQLRPNGenerator();
         parser.getCQLQuery().accept(generator);
         String q = generator.getQueryResult().toString();
-        assertEquals("{attributeSetId 1.2.840.10003.3.1, rpn {op {attrTerm {attributes {{attributeType 2, attributeValue {numeric 3}}{attributeType 3, attributeValue {numeric 3}}{attributeType 4, attributeValue {numeric 2}}{attributeType 5, attributeValue {numeric 100}}{attributeType 1, attributeValue {numeric 4}}}, term {general \"Test\"}}}}}", q);
+        assertEquals("{attributeSetId 1.2.840.10003.3.1, rpn {op {attrTerm {attributes {{attributeType 2, attributeValue {numeric 3}}{attributeType 4, attributeValue {numeric 2}}{attributeType 5, attributeValue {numeric 100}}{attributeType 1, attributeValue {numeric 4}}}, term {general \"Test\"}}}}}", q);
     }
 
     @Test
@@ -25,6 +29,19 @@ class CQL2RPNTest {
         CQLRPNGenerator generator = new CQLRPNGenerator();
         parser.getCQLQuery().accept(generator);
         String q = generator.getQueryResult().toString();
-        assertEquals("{attributeSetId 1.2.840.10003.3.1, rpn {op {attrTerm {attributes {{attributeType 2, attributeValue {numeric 3}}{attributeType 3, attributeValue {numeric 3}}{attributeType 4, attributeValue {numeric 1}}{attributeType 5, attributeValue {numeric 100}}{attributeType 1, attributeValue {numeric 4}}}, term {general \"a phrase\"}}}}}", q);
+        assertEquals("{attributeSetId 1.2.840.10003.3.1, rpn {op {attrTerm {attributes {{attributeType 2, attributeValue {numeric 3}}{attributeType 4, attributeValue {numeric 1}}{attributeType 5, attributeValue {numeric 100}}{attributeType 1, attributeValue {numeric 4}}}, term {general \"a phrase\"}}}}}", q);
+    }
+
+    @Test
+    void testWithAttribute() {
+        AttributeElement ae = new AttributeElement();
+        ae.attributeType = new ASN1Integer(2);
+        String cql = "dc.title = \"a phrase\"";
+        CQLParser parser = new CQLParser(cql);
+        parser.parse();
+        CQLRPNGenerator generator = new CQLRPNGenerator(Collections.singleton(ae));
+        parser.getCQLQuery().accept(generator);
+        String q = generator.getQueryResult().toString();
+        assertEquals("{attributeSetId 1.2.840.10003.3.1, rpn {op {attrTerm {attributes {{attributeType 2, attributeValue {numeric 3}}{attributeType 4, attributeValue {numeric 1}}{attributeType 5, attributeValue {numeric 100}}{attributeType 1, attributeValue {numeric 4}}}, term {general \"a phrase\"}}}}}", q);
     }
 }