java中StringBuilder为单线程做的，StringBuffer相反

//没有sycronized修饰method,是线程不安全的,--StringBuffer来弥补这个缺点，但速度就慢了

并没有测试出来：：

/**
 * 
 */
package com.breaver.test.string;

/**
 * @author zzf
 *@date 2017年6月22日 下午11:09:36
 */
public class TestStringBuilder implements Runnable{
    public static StringBuilder strs=new StringBuilder("my-str:");
    private String str;
    /**
     * @param args
     */
    
    public static void main(String[] args) {
        // TODO Auto-generated method stub
//        TestStringBuilder.test();
        new Thread(new TestStringBuilder("123")).start();
        new Thread(new TestStringBuilder("abc")).start();
    }
    public TestStringBuilder(String a) {
        super();
        // TODO Auto-generated constructor stub
        str=a;
    }
    @Override
    public void run() {
        // TODO Auto-generated method stub
        try{
            while(true){
                System.out.println(strs.toString());
                Thread.sleep(1000);
                strs.append(str);
            }
        }catch (Exception e) {
            // TODO: handle exception
            e.printStackTrace();
        }
    }
    public static void test(){
        StringBuilder builder =new StringBuilder();
        System.out.println(builder.toString()+":"+builder.capacity());
        builder.append("123");
        System.out.println(builder.toString()+":"+builder.capacity());
        builder.append("asssssssssssssqwqw123");
        System.out.println(builder.toString()+":"+builder.capacity()
        +"::fact-size:"+builder.length());
        builder.append("Aasssssssssssssqwqw123");
        System.out.println(builder.toString()+":"+builder.capacity()
        +"::fact-size:"+builder.length());
    }
}