FAQ of the Base64 framework in the Java library answers

Base64 is a commonly used data encoding method that is often used to transmit and store binary data in the form of readable characters.In the Java class library, there is a built -in Base64 category to implement Base64 encoding and decoding.When using the Base64 framework, some common questions may be encountered. The following are the answers to these questions and examples of Java code. Question 1: How to perform base64 encoding? To perform the base64 encoding, you can use the Base64 category `getencoder ()` method to obtain a base64.encoder object, and then use the object's `encodetostring () method to encode the binary data into the BASE64 string. The following is an example code: import java.util.Base64; public class Base64EncodingExample { public static void main(String[] args) { String text = "Hello, World!"; byte[] binaryData = text.getBytes(); Base64.Encoder encoder = Base64.getEncoder(); String encodedString = encoder.encodeToString(binaryData); System.out.println("Base64 encoded string: " + encodedString); } } The output result is: Base64 encoded string: SGVsbG8sIFdvcmxkIQ== Question 2: How to perform Base64 decoding? To perform the Base64 decoding, you can use the Base64 `GetDecoder () method to obtain a base64.DECODER object, and then use the object's` Decode () `method to decode the BASE64 string into binary data. The following is an example code: import java.util.Base64; public class Base64DecodingExample { public static void main(String[] args) { String encodedString = "SGVsbG8sIFdvcmxkIQ=="; Base64.Decoder decoder = Base64.getDecoder(); byte[] binaryData = decoder.decode(encodedString); String decodedString = new String(binaryData); System.out.println("Decoded string: " + decodedString); } } The output result is: Decoded string: Hello, World! Question 3: How to perform the BASE64 encoding of URL and file name? In the URL and file names, some characters (such as "+" and "/") may cause problems, so the BASE64 encoding of URL and file name security needs to be performed.You can use the Base64 category `Geturlencoder () method to obtain a Base64.encoder object, and then use the object 64 encoding of the URL and file name safely with the method of the object's` ENCODETOSTRING () method. The following is an example code: import java.util.Base64; public class Base64UrlEncodingExample { public static void main(String[] args) { String text = "Hello, World!"; byte[] binaryData = text.getBytes(); Base64.Encoder encoder = Base64.getUrlEncoder(); String encodedString = encoder.encodeToString(binaryData); System.out.println("URL and filename safe Base64 encoded string: " + encodedString); } } The output result is: URL and filename safe Base64 encoded string: SGVsbG8sIFdvcmxkIQ== Question 4: How to perform streaming when coding and decoding? When processing a large amount of data, loading the entire data to memory at one time can cause memory overflow.In order to avoid this, you can use the `Getencoder () and` GetDecoder () "method of Base64 category to obtain the Base64.encoder and Base64.Decoder.Code or decoding stream. The following is an example code: import java.io.ByteArrayInputStream; import java.io.ByteArrayOutputStream; import java.io.IOException; import java.util.Base64; public class Base64StreamingExample { public static void main(String[] args) throws IOException { String text = "Hello, World!"; byte[] binaryData = text.getBytes(); Base64.Encoder encoder = Base64.getEncoder(); Base64.Decoder decoder = Base64.getDecoder(); // Base64 Code flow processing ByteArrayOutputStream outputStream = new ByteArrayOutputStream(); encoder.wrap(outputStream).write(binaryData); String encodedString = outputStream.toString(); // Base64 decoding stream processing ByteArrayInputStream inputStream = new ByteArrayInputStream(encodedString.getBytes()); ByteArrayOutputStream decodedOutputStream = new ByteArrayOutputStream(); decoder.wrap(inputStream).transferTo(decodedOutputStream); String decodedString = decodedOutputStream.toString(); System.out.println("Base64 encoded string: " + encodedString); System.out.println("Base64 decoded string: " + decodedString); } } The output result is: Base64 encoded string: SGVsbG8sIFdvcmxkIQ== Base64 decoded string: Hello, World! Through the answers to the above common questions and the corresponding Java code example, I hope to help you better understand and use the Base64 framework in the Java class library.