java实战小技巧之字符串与容器互转详解

public List<String> str2list(String str, String split) {
    String[] cells = str.split(split);
    return Arrays.asList(cells);
}

public List<String> str2list2(String str, String split) {
    List<String> list = new ArrayList<>();
    Collections.addAll(list, str.split(split));
    return list;
}

public List<Integer> str2intList(String str, String split) {
    return Stream.of(str.split(split))
            .map(String::trim)
            .filter(s -> !s.isEmpty())
            .map(Integer::valueOf).collect(Collectors.toList());
}

<!-- https://mvnrepository.com/artifact/com.google.guava/guava -->
<dependency>
    <groupId>com.google.guava</groupId>
    <artifactId>guava</artifactId>
    <version>30.1-jre</version>
</dependency>

public List<String> str2list2(String str, String split) {
    return Splitter.on(split).splitToList(str);
}

public List<Integer> str2intListV2(String str, String split) {
    return Splitter.on(split).splitToStream(str)
            .map(String::trim).filter(s -> !s.isEmpty())
            .map(Integer::valueOf).collect(Collectors.toList());
}

 <dependency>
    <groupId>org.apache.commons</groupId>
    <artifactId>commons-collections4</artifactId>
    <version>4.4</version>
</dependency>

public List<Integer> str2intListV3(String str, String split) {
    List<Integer> result = new ArrayList<>();
    CollectionUtils.collect(Arrays.asList(str.split(split)), new Transformer<String, Integer>() {
        @Override
        public Integer transform(String s) {
            return Integer.valueOf(s);
        }
    }, result);
    return result;
}

 
public List<Integer> str2intListV3(String str, String split) {
    List<Integer> result = new ArrayList<>();
    CollectionUtils.collect(Arrays.asList(str.split(split)), Integer::valueOf, result);
    return result;
}

public String list2str(List<String> list, String split) {
    StringBuilder builder = new StringBuilder();
    for (String str: list) {
        builder.append(str).append(split);
    }
    return builder.substring(0, builder.length() - 1);
}

public String list2str2(List<String> list, String split) {
    return String.join(split, list);
}

public <T> String list2str3(List<T> list, String split) {
    return Joiner.on(split).join(list);
}