Question

在Java中是否可以将这两个静态函数组合成C ++模板参数的样式？我已经尝试过在类中传递，但这只是给出了不知道类型参数是什么的错误。对不起，我已经google了一下，但我是Java的新手并且很难搞清楚这个。

import com.univocity.parsers.common.processor.BeanListProcessor;
import com.univocity.parsers.tsv.TsvParser;
import com.univocity.parsers.tsv.TsvParserSettings;

import java.io.FileNotFoundException;
import java.io.FileReader;
import java.util.List;

public class Parsers {
    public static List<ThingOne> ParseThingOne(String fName) throws FileNotFoundException
    {
        BeanListProcessor<ThingOne> rowProcessor = new BeanListProcessor<ThingOne>(ThingOne.class);
        TsvParserSettings tsvSet = new TsvParserSettings();
        tsvSet.setHeaderExtractionEnabled(true);
        tsvSet.setProcessor(rowProcessor);
        TsvParser p = new TsvParser(tsvSet);
        FileReader f = new FileReader(fName);
        p.parse(f);
        return rowProcessor.getBeans();
    }

    public static List<ThingTwo> ParseThingTwo(String fName) throws FileNotFoundException
    {
        BeanListProcessor<ThingTwo> rowProcessor = new BeanListProcessor<ThingTwo>(ThingTwo.class);
        TsvParserSettings tsvSet = new TsvParserSettings();
        tsvSet.setHeaderExtractionEnabled(true);
        tsvSet.setProcessor(rowProcessor);
        TsvParser p = new TsvParser(tsvSet);
        FileReader f = new FileReader(fName);
        p.parse(f);
        return rowProcessor.getBeans();
    }
}

Answer 1

不确定为什么你说通过课程不适合你。这应该有效：

List<ThingOne> l1 = parse(ThingOne.class, "file1");
List<ThingTwo> l2 = parse(ThingTwo.class, "file2");

public static <T> List<T> parse(Class<T> clazz, String fName) throws FileNotFoundException{
    BeanListProcessor<T> rowProcessor = new BeanListProcessor<>(clazz);
    TsvParserSettings tsvSet = new TsvParserSettings();
    tsvSet.setHeaderExtractionEnabled(true);
    tsvSet.setProcessor(rowProcessor);
    TsvParser p = new TsvParser(tsvSet);
    FileReader f = new FileReader(fName);
    p.parse(f);        
    return rowProcessor.getBeans();
}

Answer 2

如果您创建一个接口或类并使您的两个类继承/扩展它，您可以使用Java Generics。例如，如果您创建一个接口MyInterface，那么： ThingOne implements MyInterface和ThingTwo implements MyInterface。然后你可以写一个通用函数如下：

public static <T extends MyInterface> List<T> ParseThing(String fName, Class<T> clazz) throws FileNotFoundException
{
    BeanListProcessor<T> rowProcessor = new BeanListProcessor<T>(clazz);
    TsvParserSettings tsvSet = new TsvParserSettings();
    tsvSet.setHeaderExtractionEnabled(true);
    tsvSet.setProcessor(rowProcessor);
    TsvParser p = new TsvParser(tsvSet);
    FileReader f = new FileReader(fName);
    p.parse(f);
    return rowProcessor.getBeans();
}

Answer 3

尝试这样的事情：

  describe Fastlane do
  describe Fastlane::FastFile do
    describe "Delete keychain Integration" do
      before :each do
        allow(File).to receive(:file?).and_return(false)
      end

      it "works with keychain name found locally" do
        allow(FastlaneCore::FastlaneFolder).to receive(:path).and_return(nil)
        keychain = File.expand_path('test.keychain')
        allow(File).to receive(:file?).and_return(false)
        allow(File).to receive(:file?).with(keychain).and_return(true)

        result = Fastlane::FastFile.new.parse("lane :test do
          delete_keychain ({
            name: 'test.keychain',
            throw_error:false
          })
        end").runner.execute(:test)

        expect(result).to eq("security delete-keychain #{keychain}")
      end

通过类似的东西调用：

public static <T> List<T> parseThing( final String fName, final BeanListProcessor<T> rowProcessor )
  throws FileNotFoundException
{
    final TsvParserSettings tsvSet = new TsvParserSettings();
    tsvSet.setHeaderExtractionEnabled(true);
    tsvSet.setProcessor(rowProcessor);
    final TsvParser p = new TsvParser(tsvSet);
    final FileReader f = new FileReader(fName);
    p.parse(f);
    return rowProcessor.getBeans();
}

Java Generic - 如何组合静态函数？

3 个答案: