Java Stream filter/peek two different conditions in the same section-CodePudding

I'm trying to filter two conditions in a stream that is inside another stream of data, what I need to do is to check if the object is there by using the "name" parameter and then reviewing the Boolean property of "isGoldplated" if is true, I tried using this code but didn't work as it wasn't filtering by the isGoldplated parameter:

List<CompressorModel> filteredCompressors = pack.getSet().getCompressors().stream()
                .peek(p -> goldData.stream().map(GoldPlateData::getCompressorSerialNo).anyMatch(name -> name.equals(p.getGcsn())))
                .peek(p -> goldData.stream().map(GoldPlateData::getIsGoldplated))
                .collect(Collectors.toList());

so I finished using two loops instead:

List<CompressorModel> filteredCompressors = new ArrayList<>();
        for (CompressorModel cmp : pack.getSet().getCompressors()) {                
            for(GoldPlateData gold: goldData) {                 
                if( StringUtils.equalsIgnoreCase(cmp.getGcsn(), gold.getCompressorSerialNo()) && Boolean.TRUE.equals(gold.getIsGoldplated())) {
                    filteredCompressors.add(cmp);
                }                   
            }               
        }

so my request is, how could I convert these two loops into a working stream?

thanks in advance

CodePudding user response：

You could use filter() on the pack.getSet().getCompressors() stream and then look for a match in goldData, like this:

List<CompressorModel> filteredCompressors = pack.getSet()
        .getCompressors().stream()
        .filter(cmp -> goldData.stream().anyMatch(gd -> cmp.getGcsn().equalsIgnoreCase(gd.getCompressorSerialNo()) && gd.getIsGoldplated()))
        .collect(Collectors.toList());

CodePudding user response：

Peek is basically there only to be used for debugging purposes. Peek can be not executed at all at times because it's a terminal operation. You can see here to get an idea.

So you may modify your implementation to use filter instead.

List<CompressorModel> filteredCompressors = pack.getSet().getCompressors().stream()
            .filter(p -> goldData.stream().map(GoldPlateData::getCompressorSerialNo).anyMatch(name -> name.equals(p.getGcsn())))
            .filter(p -> goldData.stream().map(GoldPlateData::getIsGoldplated))
            .collect(Collectors.toList());