如何在一个.properties文件的末尾添加属性

Question

I am using the below code to write a property in a .properties file.

InputStream inputStream = null;
    try {
        inputStream = file.getContents();
        Properties properties = new Properties();
        properties.load(inputStream);
        inputStream.close();
        properties.setProperty(propertyKey.trim(), propertyValue.trim());
        File file1 = file.getRawLocation().makeAbsolute().toFile();
        FileOutputStream outputStream = new FileOutputStream(file1);
        properties.store(outputStream, null);
        outputStream.close();
        }
    } catch (IOException ex) {
        ex.printStackTrace();
    } catch (CoreException ex) {
        ex.printStackTrace();
    }

Though it is adding the property in a sorted position but not at the end .But I want it will always be added at the end .How can I get that ?

Answer 1

If you check the Properties file java doc, you can find the its using HashTable to store key value pair, the order of the key is nor guaranteed. Hence you need to use File Operations once its done you need to reload the properties file.

Answer 2

Use FileWriter to append to the end of file (second parameter of constructor defines appended mode):

try (FileWriter out = new FileWriter(file, true)) {
    out.append(property + "=" + value);
}

Answer 3

FileOutputStream outputStream = new FileOutputStream(file1,true);

The true tells it to append the new content to the end of the file.

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