The path cannot be found using java

Can't find the path when using Java? don’t worry! PHP editor Xinyi provides you with a solution. During Java development, you sometimes encounter the problem that the specified path cannot be found. This may be due to incorrect file path settings or the file does not exist. This article will give you details on how to solve this problem and provide some common solutions. Let’s explore together!

Question content

The following is my code, I try to set the value in json format:

{"details": "{\"user\":\"user1\",\"password\":\"1234\"}"}

Here I have to set the data in user and pass but it is enclosed in double quotes ("").

I tried the path to detail.user but it doesn't work:

ObjectMapper mapper = new ObjectMapper(); 
ObjectNode node = (ObjectNode) mapper.readTree(new File(templatePath)); 

// System.out.println(node); 

Configuration config = Configuration.builder()
    .jsonProvider(new JacksonJsonNodeJsonProvider())
    .mappingProvider(new JacksonMappingProvider()).build(); 
    
json = JsonPath.using(config).parse(node);

for (int i = 0; i < list.size(); i++) {
    String x = list.get(i); 
    arr = x.split(": "); 
    String newHeader = arr[0].replace("|", "."); 
    
    if (newHeader.contains("[")) { 
        String nHeader = "$." + newHeader; 
        String actualVal; 
        if (arr.length >= 2) { 
            actualVal = arr[1]; 
        } else { 
            actualVal = ""; 
        } 
        json.set(nHeader, actualVal).jsonString(); 
    } else { 
        String actualVal; 
        if (arr.length >= 2) { 
            actualVal = arr[1]; 
        } else { 
            actualVal = ""; 
        } 
        json.set(newHeader, actualVal).jsonString(); 
    }
}

I try to use the above code to set the data. But I get exception.

Solution

Refer to the following code and try to update your object. You can use gson or jackson to handle json objects. Please do some work before posting a question.

import com.fasterxml.jackson.databind.JsonNode;
import com.fasterxml.jackson.databind.ObjectMapper;

public class JsonUpdateExample {

public static void main(String[] args) {
    // Sample JSON string
    String jsonString = "{\"name\":\"John\", \"age\":25, \"city\":\"New York\"}";

    // Field to update
    String fieldToUpdate = "age";
    
    // New value for the field
    int newValue = 30;

    // Update the JSON
    String updatedJson = updateJsonField(jsonString, fieldToUpdate, newValue);

    // Print the updated JSON
    System.out.println(updatedJson);
}

private static String updateJsonField(String jsonString, String fieldToUpdate, int newValue) {
    try {
        // Create ObjectMapper
        ObjectMapper objectMapper = new ObjectMapper();

        // Read the JSON string into a JsonNode
        JsonNode jsonNode = objectMapper.readTree(jsonString);

        // Update the field
        ((ObjectNode) jsonNode).put(fieldToUpdate, newValue);

        // Convert the updated JsonNode back to a JSON string
        return objectMapper.writeValueAsString(jsonNode);
    } catch (Exception e) {
        e.printStackTrace();
        return jsonString; // return the original JSON in case of an error
    }
}
}

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