How to check if multiple conditions strings exist in the csv using BufferedReader?

Question

I am using BufferedReader to check for multiple strings if they exist within a file and i am using the below script:

int n = 41; // The line number
String line;
BufferedReader br = new BufferedReader(new FileReader(context.tfilelistdir)); 
for (int i = 0; i < n; i++)
{
    line = br.readLine();
    if (line.contains("$$WORDS$$ ABC") && line.contains("$$WORDS$$ XYZ"))
    {
        do something
    }
}

Here I need to check if the string $$WORDS$$ ABC and also $$WORDS$$ XYZ both exist in different rows/cols within the csv file. BufferedReader's line does not accept &&. It only works with || (OR) condition BufferedReader overwrites the entries as it keeps reading the records.

Any way to check if both condition exist (strings exist) within the CSV file?

Answer 1

If the substrings are in different lines, some boolean flags need to be introduced to track each specific condition.

Also, it's better to use try-with-resources to ensure the file/reader resources are closed properly, and check if the file end is not reached in the reading process (then br.readLine() returns null).

int n = 41; // The line number
String line;
try (BufferedReader br = new BufferedReader(new FileReader(context.tfilelistdir))) {
    boolean foundABC = false;
    boolean foundXYZ = false;
    int i = 0;
    while ((line = br.readLine()) != null && i++ < n) { // read at most n lines

        foundABC |= line.contains("$$WORDS$$ ABC"); // will be true as soon as ABC detected
        foundXYZ |= line.contains("$$WORDS$$ XYZ"); // will be true as soon as XYZ detected
        if (foundABC && foundXYZ) { // not necessarily in the same line
            //do something
        }
    }
}