import java.util.List;
import java.util.Map;

import com.google.common.base.CharMatcher;
import com.google.common.base.Joiner;
import com.google.common.base.Preconditions;
import com.google.common.base.Splitter;
import com.google.common.base.Splitter.MapSplitter;
import com.google.common.base.Strings;
import com.google.common.collect.ImmutableList;
import com.google.common.collect.ImmutableMap;
import com.google.common.collect.Lists;


public class GuavaBase {

	public static void main(String[] args) {
		//testJoiner();
		//testSplitter();
		//testCharMatcher();
		//testPreconditions();
		
		System.out.println(Strings.commonPrefix("abc", "abcd"));
		List<String> list = Lists.newArrayList("1","2");
		System.out.println(list);
	}

	public static void testJoiner() {
		String array[] = {"1","2",null,"3"};
		String newArray = Joiner.on(";").useForNull("none").join(array);
		System.out.println(newArray);
		
		List<String> list = null;
		try {
			list = ImmutableList.of("a","b","c");
		} catch (Exception e) {
			e.printStackTrace();
		}
		String newList = Joiner.on("#").skipNulls().join(list);
		System.out.println(newList.trim());
		
		StringBuilder sb = new StringBuilder();
		Joiner joiner = Joiner.on(",").skipNulls();
		sb = joiner.appendTo(sb, "aaa",null,"bbb");
		System.out.println(sb.toString());
		
		
		Map<String,String> map = ImmutableMap.of("key1", "value1", "key2", "value2");
		String mapStr = Joiner.on(",").withKeyValueSeparator("->").join(map);
		System.out.println(mapStr);
		
	}
	
	public static void testSplitter() {
		String s = "a,b  ,c  ,d  ";
		Iterable<String> iter = Splitter.on(",").trimResults().split(s);
		System.out.println(iter);
		
		String mapS = "key1=value1,key2=value2";
		MapSplitter mapSplitter = Splitter.on(",").withKeyValueSeparator("=");
		Map<String,String> map = mapSplitter.split(mapS);
		System.out.println(map.toString());
		
		System.out.println("emptyToNull:"+Strings.emptyToNull(""));
		System.out.println("nullToEmpty:"+Strings.nullToEmpty(null));
		System.out.println("padEnd:"+Strings.padEnd("123", 5, 'a'));
		System.out.println("padStart:"+Strings.padStart("123", 5, 'b'));
		
	}
	
	public static void testCharMatcher() {
	
		String s1 = " a b  c d ";
		
		//去除多个空格
		String newS1 = CharMatcher.WHITESPACE.collapseFrom(s1, ' ');
		System.out.println(newS1);
		
		//去除首尾空格
		String newS12 = CharMatcher.WHITESPACE.trimAndCollapseFrom(s1, ' ');
		System.out.println("1"+newS12+"2");
		
		//保留数字
		String s2 = "abc123 def345 aa";
		String newS2 = CharMatcher.JAVA_DIGIT.retainFrom(s2);
		System.out.println(newS2);
		
		//保留数字和空格
		String newS22 = CharMatcher.JAVA_DIGIT.or(CharMatcher.WHITESPACE).retainFrom(s2);
		System.out.println(newS22);
	}
	
	public static void testPreconditions() {
		String s = "abc";
		String s1 = null;
		//Preconditions.checkNotNull(s1);
		
		String array[] = {"1","2","2"};
		//Preconditions.checkElementIndex(3, array.length, "描述");
		
		//Preconditions.checkArgument(100>101);
		
		Preconditions.checkState(100>101, "错了");
	}
}