as 2.0 was like java, now in 3.0, I cannot find my error in this code:
import java.io.IOException;
import java.io.OutputStreamWriter;
import java.net.Socket;
public class Main {
public static void main(String[] args){
String hostName = "localhost";
Int portNumber = 16834;
String str = "starttimer\r\n";
try {
#SuppressWarnings("resource")
Socket socket = new Socket(hostName, portNumber);
OutputStreamWriter osw = new <br>OutputStreamWriter(socket.getOutputStream(), "UTF-8");$
send(str, osw);
} catch (Exception e) {
System.err.println(e.getMessage());
}
}
static void send(String str, OutputStreamWriter o) throws IOException {
o.write(str, 0, str.length());
o.flush();
}
}
By the way dont worry about where is the data going
Obviously, it's not valid ActionScript code. It is Java. That's why you have syntax error. I suggest reading some required minimum about the ActionScript language to be able at least to distinguish it from other one before trying to implement something.
Related
Use-case:
Developers/I, want to only implement a Protobuf implementation (binary protocol). However, I need a way to add config, so, the same implementation is exposed as rest/json api as well -- without code duplication.
I have proto endpoints exposed. I also want consumers to post json equivalent of those proto objects and return/receive json equivalent of the results with type info (Pojo?). The type info helps with OpenAPI / Swagger documentation too!
What are the most elegant/simple ways to achieve that without code duplication?
Any example github code that achieves that would be helpful.
Note: This is for webflux & netty - no tomcat.
ProtobufJsonFormatHttpMessageConverter - works for tomcat, does not work for netty. A working example code would be great.
I was messing around with this and ended up with this. Nothing else worked for me.
Using protov3 and setting a protobuf like this
syntax = "proto3";
option java_package = "com.company";
option java_multiple_files = true;
message CreateThingRequest {
...
message CreateThingResponse {
....
I can scan for the protobuf files by setting app.protoPath in my application.properties
import com.fasterxml.jackson.core.JsonGenerator;
import com.fasterxml.jackson.core.JsonParser;
import com.fasterxml.jackson.databind.DeserializationContext;
import com.fasterxml.jackson.databind.JsonDeserializer;
import com.fasterxml.jackson.databind.JsonSerializer;
import com.fasterxml.jackson.databind.SerializerProvider;
import com.google.common.reflect.ClassPath;
import com.google.protobuf.Message;
import com.google.protobuf.util.JsonFormat;
import java.io.IOException;
import java.util.HashMap;
import java.util.Map;
import org.springframework.beans.factory.annotation.Value;
import org.springframework.context.annotation.Configuration;
import org.springframework.http.codec.ServerCodecConfigurer;
import org.springframework.http.codec.json.Jackson2JsonDecoder;
import org.springframework.http.codec.json.Jackson2JsonEncoder;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;
import org.springframework.web.reactive.config.WebFluxConfigurer;
#Configuration
public class WebConfig implements WebFluxConfigurer {
#Value("${app.protoPath:com.}")
private String protoPath;
#Override
public void configureHttpMessageCodecs(ServerCodecConfigurer configurer) {
configurer.defaultCodecs().jackson2JsonEncoder(
new Jackson2JsonEncoder(Jackson2ObjectMapperBuilder.json().serializerByType(
Message.class, new JsonSerializer<Message>() {
#Override
public void serialize(Message value, JsonGenerator gen, SerializerProvider serializers) throws IOException {
String str = JsonFormat.printer().omittingInsignificantWhitespace().print(value);
gen.writeRawValue(str);
}
}
).build())
);
final ClassLoader loader = Thread.currentThread().getContextClassLoader();
Map<Class<?>, JsonDeserializer<?>> deserializers = new HashMap<>();
try {
for (final ClassPath.ClassInfo info : ClassPath.from(loader).getTopLevelClasses()) {
if (info.getName().startsWith(protoPath)) {
final Class<?> clazz = info.load();
if (!Message.class.isAssignableFrom(clazz)) {
continue;
}
#SuppressWarnings("unchecked") final Class<Message> proto = (Class<Message>) clazz;
final JsonDeserializer<Message> deserializer = new CustomJsonDeserializer() {
#Override
public Class<Message> getDeserializeClass() {
return proto;
}
};
deserializers.put(proto, deserializer);
}
}
} catch (IOException e) {
throw new RuntimeException(e);
}
configurer.defaultCodecs().jackson2JsonDecoder(new Jackson2JsonDecoder(Jackson2ObjectMapperBuilder.json().deserializersByType(deserializers).build()));
}
private abstract static class CustomJsonDeserializer extends JsonDeserializer<Message> {
abstract Class<? extends Message> getDeserializeClass();
#Override
public Message deserialize(JsonParser jp, DeserializationContext ctxt) throws IOException {
Message.Builder builder = null;
try {
builder = (Message.Builder) getDeserializeClass()
.getDeclaredMethod("newBuilder")
.invoke(null);
} catch (Exception e) {
throw new RuntimeException(e);
}
JsonFormat.parser().merge(jp.getCodec().readTree(jp).toString(), builder);
return builder.build();
}
}
}
Then I just use the object types in the returns;
#PostMapping(
path = "/things",
consumes = {MediaType.APPLICATION_JSON_VALUE, "application/x-protobuf"},
produces = {MediaType.APPLICATION_JSON_VALUE, "application/x-protobuf"})
Mono<CreateThingResponse> createThing(#RequestBody CreateThingRequest request);
With https://github.com/innogames/springfox-protobuf you can get the responses to show in swagger but the requests still aren't showing for me.
You'll have to excuse the messy Java I'm a little rusty.
I needed to support json and the following code helped
#Bean
public WebFluxConfigurer webFluxConfigurer() {
return new WebFluxConfigurer() {
#Override
public void configureHttpMessageCodecs(ServerCodecConfigurer configurer) {
ObjectMapper mapper = new ObjectMapper()
.configure(DeserializationFeature.FAIL_ON_UNKNOWN_PROPERTIES, false)
.configure(SerializationFeature.FAIL_ON_EMPTY_BEANS, false)
.registerModule(new ProtobufModule());
configurer.customCodecs().register(new Jackson2JsonEncoder(mapper));
configurer.customCodecs().register(new Jackson2JsonDecoder(mapper));
}
};
}
Try adding ProtoEncoder in your WebFlux config:
#EnableWebFlux
public class MyConfig implements WebFluxConfigurer {
#Override
public void configureHttpMessageCodecs(ServerCodecConfigurer configurer) {
configurer.customCodecs().register(new ProtobufEncoder());
}
}
Then in your request mapping return the proto object:
#GetMapping (produces = "application/x-protobuf")
public MyProtoObject lookup() {
return new MyProtoObject();
}
Furthermore, if you want to serialize the proto object into JSON and return String, then have a look at com.googlecode.protobuf-java-format:protobuf-java-format library and JsonFormat::printToString capability (https://code.google.com/archive/p/protobuf-java-format/):
#GetMapping
public String lookup() {
return new JsonFormat().printToString(new MyProtoObj());
}
Since version 4.1 spring provides org.springframework.http.converter.protobuf.ProtobufHttpMessageConverter for reading and writing protos as Json.
However, If you are using Spring 5.x and Protobuf 3.x there is org.springframework.http.converter.protobuf.ProtobufJsonFormatHttpMessageConverter for more explicit conversion of Json.
This documentation should help you:
https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/http/converter/protobuf/ProtobufHttpMessageConverter.html
https://docs.spring.io/spring-framework/docs/current/javadoc-api/org/springframework/http/converter/protobuf/ProtobufJsonFormatHttpMessageConverter.html
I'm exploring reactive programming with Spring Webflux and therefore, I'm trying to make my code completely nonblocking to get all the benefits of a reactive application.
Currently my code for the method to parse a Json String to a JsonNode to get specific values (in this case the elementId) looks like this:
public Mono<String> readElementIdFromJsonString(String jsonString){
final JsonNode jsonNode;
try {
jsonNode = MAPPER.readTree(jsonString);
} catch (IOException e) {
return Mono.error(e);
}
final String elementId = jsonNode.get("elementId").asText();
return Mono.just(elementId);
}
However, IntelliJ notifies me that I'm using an inappropriate blocking method call with this code:
MAPPER.readTree(jsonString);
How can I implement this code in a nonblocking way? I have seen that since Jackson 2.9+, it is possible to parse a Json String in a nonblocking async way, but I don't know how to use that API and I couldn't find an example how to do it correctly.
I am not sure why it is saying it is a blocking call since Jackson is non blocking as far as I know. Anyway one way to resolve this issue is to use schedulers if you do not want to use any other library. Like this.
public Mono<String> readElementIdFromJsonString(String input) {
return Mono.just(Mapper.readTree(input))
.map(it -> it.get("elementId").asText())
.onErrorResume( it -> Mono.error(it))
.subscribeOn(Schedulers.boundedElastic());
}
Something along that line.
import reactor.core.publisher.Mono;
import java.nio.charset.StandardCharsets;
import org.springframework.core.ResolvableType;
import org.springframework.core.io.buffer.DataBufferUtils;
import org.springframework.core.io.buffer.DefaultDataBuffer;
import org.springframework.core.io.buffer.DefaultDataBufferFactory;
import org.springframework.http.codec.json.AbstractJackson2Decoder;
import org.springframework.util.MimeType;
import org.springframework.util.MimeTypeUtils;
import com.fasterxml.jackson.databind.ObjectMapper;
#FunctionalInterface
public interface MessageParser<T> {
Mono<T> parse(String message);
}
public class JsonNodeParser extends AbstractJackson2Decoder implements MessageParser<JsonNode> {
private static final MimeType MIME_TYPE = MimeTypeUtils.APPLICATION_JSON;
private static final ObjectMapper OBJECT_MAPPER = allocateDefaultObjectMapper();
private final DefaultDataBufferFactory factory;
private final ResolvableType resolvableType;
public JsonNodeParser(final Environment env) {
super(OBJECT_MAPPER, MIME_TYPE);
this.factory = new DefaultDataBufferFactory();
this.resolvableType = ResolvableType.forClass(JsonNode.class);
this.setMaxInMemorySize(100000); // 1MB
canDecodeJsonNode();
}
#Override
public Mono<JsonNode> parse(final String message) {
final byte[] bytes = message.getBytes(StandardCharsets.UTF_8);
return decode(bytes);
}
private Mono<JsonNode> decode(final byte[] bytes) {
final DefaultDataBuffer defaultDataBuffer = this.factory.wrap(bytes);
return this.decodeToMono(Mono.just(defaultDataBuffer), this.resolvableType, MIME_TYPE, Map.of())
.ofType(JsonNode.class)
.subscribeOn(Schedulers.boundedElastic())
.doFinally((t) -> DataBufferUtils.release(defaultDataBuffer));
}
private void canDecodeJsonNode() {
if (!canDecode(this.resolvableType, MIME_TYPE)) {
throw new IllegalStateException(String.format("JsonNodeParser doesn't supports the given tar`enter code here`get " +
"element type [%s] and the MIME type [%s]", this.resolvableType, MIME_TYPE));
}
}
}
We have aes-256 encryption for some data in one of the tables and we are migrating this to sql server. The problem is that we cannot decrypt the data in sql server due to incompatibility. Is there any way we can encrypt data in MYSQL in a way which is compatible with sql server aswell. Any advise ?
if you know the secretkey then you can decrypt the data see following code for encryption and decryption of AES-256 . the code is written in JAVA
check this link AES-256 Password Based Encryption/Decryption in Java
import java.security.AlgorithmParameters;
import java.security.NoSuchAlgorithmException;
import java.security.SecureRandom;
import javax.crypto.BadPaddingException;
import javax.crypto.Cipher;
import javax.crypto.IllegalBlockSizeException;
import javax.crypto.SecretKey;
import javax.crypto.SecretKeyFactory;
import javax.crypto.spec.IvParameterSpec;
import javax.crypto.spec.PBEKeySpec;
import javax.crypto.spec.SecretKeySpec;
import javax.xml.bind.DatatypeConverter;
public class EncryptionDecryption {
private static String salt;
private static int iterations = 65536 ;
private static int keySize = 256;
private static byte[] ivBytes;
private static SecretKey secretKey;
public static void main(String []args) throws Exception {
salt = getSalt();
char[] message = "PasswordToEncrypt".toCharArray();
System.out.println("Message: " + String.valueOf(message));
System.out.println("Encrypted: " + encrypt(message));
System.out.println("Decrypted: " + decrypt(encrypt(message).toCharArray()));
}
public static String encrypt(char[] plaintext) throws Exception {
byte[] saltBytes = salt.getBytes();
SecretKeyFactory skf = SecretKeyFactory.getInstance("PBKDF2WithHmacSHA1");
PBEKeySpec spec = new PBEKeySpec(plaintext, saltBytes, iterations, keySize);
secretKey = skf.generateSecret(spec);
SecretKeySpec secretSpec = new SecretKeySpec(secretKey.getEncoded(), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.ENCRYPT_MODE, secretSpec);
AlgorithmParameters params = cipher.getParameters();
ivBytes = params.getParameterSpec(IvParameterSpec.class).getIV();
byte[] encryptedTextBytes = cipher.doFinal(String.valueOf(plaintext).getBytes("UTF-8"));
return DatatypeConverter.printBase64Binary(encryptedTextBytes);
}
public static String decrypt(char[] encryptedText) throws Exception {
System.out.println(encryptedText);
byte[] encryptedTextBytes = DatatypeConverter.parseBase64Binary(new String(encryptedText));
SecretKeySpec secretSpec = new SecretKeySpec(secretKey.getEncoded(), "AES");
Cipher cipher = Cipher.getInstance("AES/CBC/PKCS5Padding");
cipher.init(Cipher.DECRYPT_MODE, secretSpec, new IvParameterSpec(ivBytes));
byte[] decryptedTextBytes = null;
try {
decryptedTextBytes = cipher.doFinal(encryptedTextBytes);
} catch (IllegalBlockSizeException e) {
e.printStackTrace();
} catch (BadPaddingException e) {
e.printStackTrace();
}
return new String(decryptedTextBytes);
}
public static String getSalt() throws Exception {
SecureRandom sr = SecureRandom.getInstance("SHA1PRNG");
byte[] salt = new byte[20];
sr.nextBytes(salt);
return new String(salt);
}
}
My java program is storing the content of web page in the string sb and I want to parse the string to HTML DOM. How do I do that?
import java.io.IOException;
import java.io.InputStream;
import java.io.StringReader;
import java.net.*;
import javax.xml.parsers.DocumentBuilder;
import javax.xml.parsers.DocumentBuilderFactory;
import javax.xml.parsers.ParserConfigurationException;
import org.w3c.dom.Document;
import org.w3c.dom.Element;
import org.xml.sax.InputSource;
import org.xml.sax.SAXException;
public class Scraper {
public static void main(String[] args) throws IOException, SAXException {
URL u;
try {
u = new URL("https://twitter.com/ssjsatish");
URLConnection cn = u.openConnection();
System.out.println("content type: "+cn.getContentType());
InputStream is = cn.getInputStream();
long l = cn.getContentLengthLong();
StringBuilder sb = new StringBuilder();
if (l!=0) {
int c;
while ((c = is.read()) != -1) {
sb.append((char)c);
}
is.close();
System.out.println(sb);
DocumentBuilder db = DocumentBuilderFactory.newInstance().newDocumentBuilder();
InputSource i = new InputSource();
i.setCharacterStream(new StringReader(sb.toString()));
Document doc = db.parse(i);
}
} catch (MalformedURLException e) {
e.printStackTrace();
} catch (ParserConfigurationException e) {
e.printStackTrace();
}
}
}
You don't want to use an XML parser to parse HTML, because not all valid HTML is valid XML. I would recommend using a library specifically designed to parse "real-world" HTML, for example I have had good results with jsoup, but there are others. Another advantage of using this sort of library is that their APIs are designed with Web Scraping in mind, and provide much simpler ways of accessing data in the HTML document.
I have created a MySQL database with entries similar to nurse roster, Now i need to send this data to optaplanner deployed on my server. To which file do i need to send it in the optaplanner folder deployed on server to get the results displayed on my webpage.
I'm using Xstream to generate XML file.
Can any one please give me brief on how to make this functionality work and get me the desired results.
The whole dataset serialization from and to XML is part of optaplanner-examples: OptaPlanner itself doesn't provide or require any serialization format. That being said, optaplanner-examples includes the following serialization formats:
Every example: XStream XML format in data directories unsolved and solved. The format is defined by the XStream annotations (#XStreamAlias etc) on the domain classes. In some cases the XML format is too verbose, causing OutOfMemoryError, for example for the big MachineReassignment B datasets.
Most examples: Competition specific TXT format in data directories import and export. The format is defined by the competition (see docs). In the examples GUI, click on button Import to load them.
I suggested you to read the final chapter in optaplanner manual / documentation :
Chapter 15. Integration
If your data source is a database, you can annotate your domain POJO's with JPA annotations. I think it will be a waste if you still store the data from database to xml file then feed the xml file to optaplanner, it will be more wise to feed your POJO objects to optaplanner directly.
I don't know what your web application technology, but the general algorithm will be like this :
Get POJO object data from your database (you can use JPA etc.)
Construct the solution class object
Feed the solution object to optaplanner solver
Get the best solution from optaplanner solver and present it to your user in your user desire.
Take a look at CloudBalancingHelloWorld.java class to get the basic idea. Hope this can help you.
package com.jdbcxml;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.w3c.dom.Document;
class EmployeeDAO
{
private Connection conn = null;
static
{
try
{
Class.forName("com.mysql.jdbc.Driver");
}
catch (Exception e)
{
e.printStackTrace();
}
}
public EmployeeDAO()
{
String url = "jdbc:mysql://50.62.23.184:3306/gtuser";
String userId = "gtuser1";
String passWord = "";
try
{
conn = DriverManager.getConnection(url, userId, passWord);
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public void finalize()
{
try
{
conn.close();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public Document getCustomerList()
{
Document doc = null;
try
{
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * from t7_users");
doc = JDBCUtil.toDocument(rs);
rs.close();
stmt.close();
}
catch (Exception e)
{
e.printStackTrace();
}
return doc;
}
public String getCustomerListAsString()
{
String xml = null;
try
{
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * from t7_users");
xml = JDBCUtil.toXML(rs);
rs.close();
stmt.close();
}
catch (Exception e)
{
e.printStackTrace();
}
return xml;
}
public static void main(String argv[]) throws Exception
{
EmployeeDAO dao = new EmployeeDAO();
String xml = dao.getCustomerListAsString();
System.out.println(xml);
Document doc = dao.getCustomerList();
System.out.println(doc);
//PrintWriter out = new PrintWriter(new FileWriter("output.txt"));
//out.write(doc);;
//out.close();
}
}
Here the pseudo code (I never actually use JSP, I currently using GWT) to give you the basic idea, but please do remember these notes :
I think it will be a waste to save your POJO objects to xml then use XStream library to extract it again to POJO objects. In optaplanner example, they use it because it only need a static data and for the sake of example.
I assume that you already create your approriate domain class model that fit your planning problem domain. Because this is one of the core concept of optaplanner.
In method generateCustomerRoster, you should put your own logic to convert your customer POJO objects to planning solution object.
Hope this can help you and lead you to finish your job. Thanks & Regards.
package com.jdbcxml;
import java.io.FileOutputStream;
import java.io.FileWriter;
import java.io.PrintStream;
import java.io.PrintWriter;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import org.w3c.dom.Document;
public class EmployeeDAO
{
private Connection conn = null;
static
{
try
{
Class.forName("com.mysql.jdbc.Driver");
}
catch (Exception e)
{
e.printStackTrace();
}
}
public EmployeeDAO()
{
String url = "jdbc:mysql://50.62.23.184:3306/gtuser";
String userId = "gtuser1";
String passWord = "";
try
{
conn = DriverManager.getConnection(url, userId, passWord);
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public void finalize()
{
try
{
conn.close();
}
catch (SQLException e)
{
e.printStackTrace();
}
}
public List<Customer> getCustomerList()
{
Document doc = null;
try
{
Statement stmt = conn.createStatement();
ResultSet rs = stmt.executeQuery("SELECT * from t7_users");
doc = JDBCUtil.toDocument(rs);
rs.close();
stmt.close();
}
catch (Exception e)
{
e.printStackTrace();
}
return doc;
}
public CustomerRoster generateCustomerRoster(List<Customer> rawData) {
CustomerRoster result = new CustomerRoster();
// here you should write your logic to generate Customer Roster data from your Raw Data (Customer)
return result;
}
public static void main(String argv[]) throws Exception
{
// Build the Solver
SolverFactory solverFactory = SolverFactory.createFromXmlResource("yourSolverConfig.xml");
Solver solver = solverFactory.buildSolver();
// Load your problem
EmployeeDAO dao = new EmployeeDAO();
List<Customer> listCustomer = dao.getCustomerList();
CustomerRoster unsolvedCustomerRoster = generateCustomerRoster(listCustomer);
// Solve the problem
solver.solve(unsolvedCustomerRoster);
CustomerRoster solvedCustomerRoster = (CustomerRoster) solver.getBestSolution();
// Display the result
DataGrid grid = new DataGrid(solvedCustomerRoster); // Just change this line code to display to any of your view component
}
}