google guava 测试

亦凉 2022-07-28 00:13 229阅读 0赞

HashMultiset 统计单词次数

import com.google.common.collect.HashMultiset;
    	import com.google.common.collect.Multiset.Entry;
    
    	/**
    	* 
    	*  统计一个词在文档中出现了多少次
    	*/
        public static void main(String[] args) throws Exception{
        	
        	HashMultiset<String> multiset = HashMultiset.create();
        	multiset.add("hello");
        	multiset.add("hello");
        	multiset.add("word");
        	multiset.add("hello");
        	multiset.add("hello");
        	
        	// 方法一遍历
        	System.out.println("---------------------方法一遍历----------------------");
        	for(Entry<String> entry : multiset.entrySet()){
        		System.out.println(entry.getElement()+"出现："+entry.getCount()+"次");
        	}
        	
        	// 方法二遍历
        	System.out.println("---------------------方法二遍历----------------------");
        	for(String word : multiset.elementSet()){
        		System.out.println(word+"出现："+multiset.count(word)+"次");
        	}
        	
        	System.out.println("----------------------统计总数-----------------------");
        	System.out.println("一共有" +multiset.size()+"个单词");
        }

输出

---------------------方法一遍历----------------------
    hello出现：4次
    word出现：1次
    ---------------------方法二遍历----------------------
    hello出现：4次
    word出现：1次
    ----------------------统计总数-----------------------
    一共有5个单词

2. 示列代码

import com.google.common.collect.HashMultiset;
    import com.google.common.collect.Lists;
    import com.google.common.collect.Multiset;
    
    import java.util.List;
    
    public class MutisetTest {
    
        public static final List<String> collection = Lists.newArrayList("yellow", "red", "yellow", "yellow");
    
        public static void main(String[] args) {
            Multiset<String> set = HashMultiset.create();
            for (String key : collection) {
                set.add(key);
            }
            int yellowCount = set.count("yellow");
            System.out.println(String.format("yellow count=%s", yellowCount));
            System.out.println(String.format("total count=%s", set.size()));
            System.out.println(set.toString());
    
            for (String key : set) {
                System.out.println(String.format("set value=%s", key));
            }
        }
    }

输出：

yellow count=3
    total count=4
    [red, yellow x 3]
    set value=red
    set value=yellow
    set value=yellow
    set value=yellow

Files 操作文件

import java.io.File;
    import java.io.IOException;
    
    import com.google.common.base.Charsets;
    import com.google.common.collect.HashMultiset;
    import com.google.common.collect.ImmutableList;
    import com.google.common.collect.Multiset.Entry;
    import com.google.common.io.Files;
    
    /**
     * guava 测试类
     * 
     * @author zhengyong
     *
     */
    public class TestGuava {
    	
    	public static void main(String[] args) throws Exception {
    		
    		testFiles();
    	}
    	
    	/**
    	 * google Guava Files 测试
    	 * @throws IOException
    	 */
    	private static void testFiles() throws IOException {
    		String textFilePath = "/Users/zhengyong/test.txt";
    		File file = new File(textFilePath);
    		
    		System.out.println("---------------------方式一读取文件内容----------------------");
    		String content1 = Files.asCharSource(file, Charsets.UTF_8).read();
    		System.out.println(content1);
    		
    		System.out.println("---------------------方式二读取文件内容----------------------");
    		String content2 = Files.asByteSource(file).asCharSource(Charsets.UTF_8).read();
    		System.out.println(content2);
    		
    		// 读取字节流 - 读取文件流，并写向另外一个文件
    		File fileForm = new File("/Users/zhengyong/testFile.jpg");
    		File fileDest = new File("/Users/zhengyong/Files.png");
    		byte[] bytes = Files.asByteSource(fileForm).read();
    		Files.write(bytes, fileDest);
    		
    		System.out.println("---------------------方式三按行读取文件内容----------------------");
    		ImmutableList<String> lines = Files.asCharSource(file, Charsets.UTF_8).readLines();
    		for (int i = 0, length = lines.size(); i < length; i++) {
    			System.out.println("第" + i + "行：" + lines.get(i));
    		}
    		
    	}
    }

结果：

---------------------方式一读取文件内容----------------------
    hello word
    test google guava Fiels class
    
    ---------------------方式二读取文件内容----------------------
    hello word
    test google guava Fiels class
    
    ---------------------方式三按行读取文件内容----------------------
    第0行：hello word
    第1行：test google guava Fiels class

参考地址

[http://ifeve.com/google-guava/][http_ifeve.com_google-guava]

[http_ifeve.com_google-guava]: http://ifeve.com/google-guava/