【java】有效工具方法

 

1.List/Set/Sets.SetView<String>等Iterable子类的集合转化为,分隔的字符串

<dependency>
    　　<groupId>com.google.guava</groupId>
    　　<artifactId>guava</artifactId>
    　　<version>23.0</version>
</dependency>

import com.google.common.base.Joiner;

Joiner.on(",").join(list);

 

 

2.Java MD5 加密

 

<!--commons-lang3 工具类  https://mvnrepository.com/artifact/org.apache.commons/commons-lang3 -->
        <dependency>
            <groupId>org.apache.commons</groupId>
            <artifactId>commons-lang3</artifactId>
        </dependency>
        <dependency>
            <groupId>commons-collections</groupId>
            <artifactId>commons-collections</artifactId>
            <version>3.2.1</version>
        </dependency>
        <dependency>
            <groupId>commons-codec</groupId>
            <artifactId>commons-codec</artifactId>
        </dependency>

 

　import org.apache.commons.codec.digest.DigestUtils;

String s = DigestUtils.md5Hex(str);

 

 

 

 

 

 

 

3.