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Escape Character Utility per dati URL e JSON: sentiti libero di usarlo nel tuo progetto Java

Pubblicato: 2021-11-19
Escape Character Utility per dati URL e JSON - Sentiti libero di usarlo nel tuo progetto Java

Cos'è il carattere di escape in Java?

Principalmente i caratteri di escape sono i caratteri which replaces existing character con un carattere new & provided character che funziona meglio senza generare alcun errore in fase di esecuzione.

Inoltre, è richiesto per la trasmissione tra sistemi/processi, ovvero lo stesso char funziona per C++, Java, ecc.

In questo tutorial esamineremo due Escape Character Utilities.

  1. URLEscapeUtil
  2. JSONEscapeUtil

Anche questo tutorial ti aiuterà se hai le seguenti domande:

  • Caratteri di escape Java nella stringa
  • Quali caratteri devono essere sottoposti a escape su HTML
  • Cosa significa escape char in Java
  • Caratteri di escape Java nella stringa
  • Come faccio a sfuggire a una stringa per Java?
  • Sequenze di escape in Java con esempi

Iniziamo:

  1. Crea classe CrunchifyEscapeCharUtility.java
  2. Crea il metodo crunchifyURLEscapeUtil(String s) – che restituisce String con il carattere di escape nell'URL fornito
  3. Crea il metodo crunchifyJSONEscapeUtil(String s) – che restituisce String con il carattere di escape nel JSON fornito
  4. In principale() –
    1. leggeremo i dati JSON dal file
    2. fornire il nome del file è Crunchify_Escape_Util.txt
  5. Usiamo java.net.URLEncoder per aggiungere il carattere di escape dell'URL

In Java, quando codifichiamo una stringa, si applicano le seguenti regole:

codificare una stringa, le seguenti regole - Crunchify

Ecco il contenuto del file Crunchify_Escape_Util.txt . Inseriscilo nel tuo laptop/desktop e aggiorna la posizione del percorso nel programma.

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{
     "founder" : "App Shah" ,
     "blogURL" : "https://crunchify.com" ,
     "twitter" : "https://twitter.com/Crunchify" ,
     "social" : {
         "facebook" : "http://facebook.com/Crunchify" ,
         "pinterest" : "https://www.pinterest.com/Crunchify/crunchify-articles”,
        " rss ": " https : //crunchify.com/feed/"
     }
}

Opzione-1: ecco un esempio Java completo.

  • Crea i nostri metodi Escape JSON e URL.
Java
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package crunchify . com . tutorials ;
 
import java . io . BufferedReader ;
import java . io . FileReader ;
import java . io . IOException ;
import java . net . URLEncoder ;
import java . nio . charset . StandardCharsets ;
import java . text . StringCharacterIterator ;
 
/**
* @author Crunchify.com
* Version: 1.0
* Program: Escape Character Utility for URL and JSON data - Feel free to use in your Java Project.
*/
 
public class CrunchifyEscapeCharUtility {
 
     public static void main ( String [ ] args ) {
 
         // URL Escape Utility
         String crunchifyURL = "https://crunchify.com/this is test" ;
         crunchifyLog ( "Sample URL: " + crunchifyURL ) ;
         crunchifyLog ( "Escaped URL: " + crunchifyURLEscapeUtil ( crunchifyURL ) ) ;
 
         // JSON Escape Utility
         // We will read file first and then we will do escape char on that
         StringBuilder jsonData = new StringBuilder ( ) ;
         BufferedReader crunchifyBufferReader = null ;
         try {
             String crunchifyLine ;
             crunchifyBufferReader = new BufferedReader (
                     new FileReader ( "/Users/app/Downloads/Crunchify_Escape_Util.txt" ) ) ;
             while ( ( crunchifyLine = crunchifyBufferReader . readLine ( ) ) ! = null ) {
                 jsonData . append ( crunchifyLine ) . append ( "\n" ) ;
             }
 
             // IOException: Signals that an I/O exception of some sort has occurred.
             // This class is the general class of exceptions produced by failed or interrupted I/O operations.
         } catch ( IOException exception ) {
             exception . printStackTrace ( ) ;
         } finally {
             try {
                 if ( crunchifyBufferReader ! = null )
                     crunchifyBufferReader . close ( ) ;
             } catch ( IOException ex ) {
                 ex . printStackTrace ( ) ;
             }
         }
 
         // Let's print raw JSON file data
         crunchifyLog ( "\n Sample JSON: " + jsonData . toString ( ) . toString ( ) ) ;
 
         // Let's print data after escaping JSON strings
         crunchifyLog ( "Escaped JSON: " + crunchifyJSONEscapeUtil ( jsonData . toString ( ) . toString ( ) ) ) ;
 
     }
 
     // Used to ensure that HTTP query strings are in proper form, by escaping special characters such as spaces.
     // Translates a string into application/x-www-form-urlencoded format using a specific encoding scheme
     public static String crunchifyURLEscapeUtil ( String crunchifyURL ) {
         String crunchifyNewURL ;
 
// UTF_8: Eight-bit UCS Transformation Format.
crunchifyNewURL = URLEncoder . encode ( crunchifyURL , StandardCharsets . UTF_8 ) ;
return crunchifyNewURL ;
     }
 
     // JSON Escape Utility
     public static String crunchifyJSONEscapeUtil ( String crunchifyJSON ) {
 
// StringBuilder(): Constructs a string builder with no characters in it and an initial capacity of 16 characters.
         final StringBuilder crunchifyNewJSON = new StringBuilder ( ) ;
 
         // StringCharacterIterator class iterates over the entire String
         StringCharacterIterator crunchifyIterator = new StringCharacterIterator ( crunchifyJSON ) ;
 
// current(): Implements CharacterIterator.current() for String.
         char crunchifyChar = crunchifyIterator . current ( ) ;
 
         // DONE = \\uffff (not a character)
         while ( crunchifyChar ! = StringCharacterIterator . DONE ) {
             if ( crunchifyChar == '\"' ) {
                 crunchifyNewJSON . append ( "\\\" ");
            } else if (crunchifyChar == '\t') {
                crunchifyNewJSON.append(" \ \ t ");
            } else if (crunchifyChar == '\f') {
                crunchifyNewJSON.append(" \ \ f ");
            } else if (crunchifyChar == '\n') {
                crunchifyNewJSON.append(" \ \ n ");
            } else if (crunchifyChar == '\r') {
                crunchifyNewJSON.append(" \ \ r ");
            } else if (crunchifyChar == '\\') {
                crunchifyNewJSON.append(" \ \ \ \ ");
            } else if (crunchifyChar == '/') {
                crunchifyNewJSON.append(" \ \ / ");
            } else if (crunchifyChar == '\b') {
                crunchifyNewJSON.append(" \ \ b " ) ;
             } else {
 
                 // Nothing matched - just as text as it is.
// next(): Implements CharacterIterator.next() for String.
                 crunchifyNewJSON . append ( crunchifyChar ) ;
             }
             crunchifyChar = crunchifyIterator . next ( ) ;
         }
         return crunchifyNewJSON . toString ( ) ;
     }
 
     // Simple log utility
     private static void crunchifyLog ( String crunchifyData ) {
 
System . out . println ( crunchifyData ) ;
     }
 
}

Uscita console Eclipse:

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Sample URL : https : //crunchify.com/this is test
Escaped URL : https % 3A % 2F % 2Fcrunchify.com % 2Fthis + is + test
 
Sample JSON : {
     "founder" : "App Shah" ,
     "blogURL" : "https://crunchify.com" ,
     "twitter" : "https://twitter.com/Crunchify" ,
     "social" : {
         "facebook" : "http://facebook.com/Crunchify" ,
         "pinterest" : "https://www.pinterest.com/Crunchify/crunchify-articles”,
        " rss ": " https : //crunchify.com/feed/"
     }
}
 
Escaped JSON : { \ n      \ " founder \ " : \ " App Shah \ " , \ n      \ " blogURL \ " : \ " https : \ / \ / crunchify . com \ " , \ n     
\ " twitter \ " : \ " https : \ / \ / twitter . com \ / Crunchify \ " , \ n      \ " social \ " : { \ n          \ " facebook \ " :
\ " http : \ / \ / facebook . com \ / Crunchify \ " , \ n          \ " pinterest \ " : \ " https : \ / \ / www . pinterest . com \ / Crunchify \ / crunchify - articles ” ,
\ n          \ " rss \ " : \ " https : \ / \ / crunchify . com \ / feed \ / \ " \ n      } \ n } \ n
 
Process finished with exit code 0

Opzione-2: utilizzo della dipendenza commons-text di Apache Common

  • Aggiungi la dipendenza pom.xml di Maven
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       < dependency >
             < groupId > org . apache . commons < / groupId >
             < artifactId > commons - text < / artifactId >
             < version > 1.9 < / version >
         < / dependency >

Codice completo:

  • Crea classe: CrunchifyEscapeJSONTutorial.java
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package crunchify . com . java . tutorials ;
 
import org . apache . commons . text . StringEscapeUtils ;
 
/**
* @author Crunchify.com
* Program: In Java How to Escape JSON? Simple Tutorial using Apache Commons Library.
*/
 
public class CrunchifyEscapeJSONTutorial {
 
     public static void main ( String [ ] args ) {
 
         // StringEscapeUtils: Escapes and unescapes Strings for Java, Java Script, HTML and XML.
         // #ThreadSafe#
         // This code has been adapted from Apache Commons Lang 3.5.
 
         String crunchifyHTML = "{\n" +
                 "    \"founder\": \"App Shah\",\n" +
                 "    \"blogURL\": \"https://crunchify.com\",\n" +
                 "    \"twitter\": \"https://twitter.com/Crunchify\",\n" +
                 "    \"social\": {\n" +
                 "        \"facebook\": \"http://facebook.com/Crunchify\",\n" +
                 "        \"pinterest\": \"https://www.pinterest.com/Crunchify/crunchify-articles”,\n" +
                 "        \"rss\": \"https://crunchify.com/feed/\"\n" +
                 "    }\n" +
                 "}" ;
 
         // escapeJson: Escapes the characters in a String using Json String rules.
         // Escapes any values it finds into their Json String form. Deals correctly with quotes and control-chars (tab, backslash, cr, ff, etc.)
 
         // So a tab becomes the characters '\\' and 't'.
         // The only difference between Java strings and Json strings is that in Json, forward-slash (/) is escaped.
         String crunchifyResult = StringEscapeUtils . escapeJson ( crunchifyHTML ) ;
 
         crunchifyPrintUtils ( crunchifyResult ) ;
 
     }
 
     private static void crunchifyPrintUtils ( String crunchifyResult ) {
         System . out . println ( crunchifyResult ) ;
     }
}
 

IntelliJ IDEA Risultato:

Siamo passati a IntelliJ IDEA negli ultimi due anni. Ecco un risultato della console.

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{ \ n      \ " founder \ " : \ " App Shah \ " , \ n      \ " blogURL \ " : \ " https : \ / \ / crunchify . com \ " , \ n      \ " twitter \ " : \ " https : \ / \ / twitter . com \ / Crunchify \ " , \ n      \ " social \ " : { \ n          \ " facebook \ " : \ " http : \ / \ / facebook . com \ / Crunchify \ " , \ n          \ " pinterest \ " : \ " https : \ / \ / www . pinterest . com \ / Crunchify \ / crunchify - articles \ u201D , \ n          \ " rss \ " : \ " https : \ / \ / crunchify . com \ / feed \ / \ " \ n      } \ n }
 
Process finished with exit code 0

Fammi sapere se riscontri problemi durante l'esecuzione di questa applicazione Java.