java常见的基础组件

功能

示例

字符串空判断

StringUtils.isEmpty(null)， StringUtils.isBlank(" ")

字符串trim

StringUtils.trim(" abc "), StringUtils.strip("  abc", "xyz")

字符串分割

String[] r01 = StringUtils.split("  abc dd")

String[] r02 = StringUtils.split("abc,dd", ",")

StringUtils.splitPreserveAllTokens(str4, ",")

数组元素拼接  

StringUtils.join(array, ",")

随机数

RandomStringUtils.randomAscii(10)

数组操作

ArrayUtils.clone(arr)

ArrayUtils.isEmpty(arr)

ArrayUtils.toObject(array10)

日期

DateUtils.parseDate("2010/01/01 11:22:33", new String[]{"yyyy-MM-dd HH:mm:ss"})

基本反射工具

BeanUtils.getProperty(bean, "name")

SampleBean newBean = (SampleBean) BeanUtils.cloneBean(bean);

BeanUtils.describe(bean); //获得注解

BeanUtils.populate(bean, map);//填充数据

String[] array = BeanUtils.getArrayProperty(bean, "array");//获取数组     

String value = BeanUtils.getNestedProperty(bean, "nestedBean.nestedProperty")

BeanUtils.setProperty(bean8, "url", "http://www.google.com/");

DateConverter converter = new DateConverter();

converter.setPattern("yyyy/MM/dd HH:mm:ss");

ConvertUtils.register(converter, Date.class);

ConvertUtils.register(converter, String.class);

BeanUtils.setProperty(bean9, "date", "2010/12/19 23:40:00");

实现equals等方法

public boolean equals(Object obj) {

return EqualsBuilder.reflectionEquals(this, obj);  }

InvokeMethod

Main main = new Main();

Child child = new Child();

MethodUtils.invokeMethod(main, "pass", child); // OK

MethodUtils.invokeExactMethod(child, "pass', child);

lang.time.*

FastDateFormat相对于SimpleDateFormat是线程安全的

功能

示例

复写常用Object方法

Objects.equal(null, null)

Objects.hashCode(person)

Objects.toStringHelper(Person.class)

ComparisonChain.start().compare(name, other.name).result();

Throwables

Throwable getRootCause(Throwable)

List<Throwable> getCausalChain(Throwable)

String getStackTraceAsString(Throwable)

Immutable不可变集合

很好的防御编程（defensive programming）的技术实践

常见集合Colletion,List，Set,SortedSet,Map,SortedMap都有其对应类型

其他

Strings. Range, EventBus, Caches, null值的管理(java的一个痛点)

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pre>List<String> orderNumberList = Lists.transform(orderList,

Function<TrainOrderInfo, String>

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li>

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获取某一日期当月第一天的日期部分

：DateTime curMonth1 = DateTime.now().dayOfMonth().withMinimumValue().withTimeAtStartOfDay();

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br> System.out.println(result.withTimeAtStartOfDay());

br> System.out.println(result.plusDays(1).withTimeAtStartOfDay());

br> System.out.println(result.plusWeeks(1).dayOfWeek().withMinimumValue().withTimeAtStartOfDay());

br> System.out.println(temp);

br> System.out.println(result.plusMonths(1).dayOfMonth().withMinimumValue().withTimeAtStartOfDay());

br> System.out.println(new Date(temp.getMillis()));

img src="https://images2015.cnblogs.com/blog///--.png" alt="">

li>

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3扳斧

，Web提供用户入口，SOA服务提供核心服务，Job完成各类脏活累活，其他的主要起到辅助作用）

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li>

/li>

/span>

li>

/li>

SLF4J就是一个日志接口标准

，无论是log4j2，logback，提供的都是其实现，对开发透明，非常方便的进行插件式管理。这部分需要依赖4个组件，分别是：slf4j-api接口；log4j-api，log4j-core，log4j-slf4j-impl实现

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li>服务框架

/li>

strong>CXF

/strong>已经成为JAVA SOA服务的实际标准，其轻量化的特点深入人心，此外，其与Spring可以更好的结合。

li> job框架

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li>测试工具

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li>HttpClient

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 1 @RequestMapping("/image/{url}")  2 public void getImage(@PathVariable String url, HttpServletResponse response)  3 throws ClientProtocolException, IOException {  4 String realurl = new String(Base64.decodeBase64(url));  5  6 InputStream instream = FileWSManagerUtil.getImage(realurl);  7 OutputStream outputStream = null;  8 response.setContentType("image/jpeg");  9 try { 10 outputStream = response.getOutputStream(); 11 byte[] buffer = new byte[8192]; 12 int count; 13 while ((count = instream.read(buffer)) > 0) { 14 outputStream.write(buffer, 0, count); 15  } 16 } finally { 17  FileIO.close(outputStream); 18  FileIO.close(instream); 19  } 20  } 21 22 private static InputStream get(String targetURL) { 23 HttpGet request = new HttpGet(targetURL); 24 request.setHeader("Authorization", "Basic " + authorization); 25 try { 26 HttpResponse response = HttpClients.createDefault().execute(request); 27 if (response.getStatusLine().getStatusCode() == 200) 28 return response.getEntity().getContent(); 29 } catch (Exception ex) { 30 logger.warn("图片获取失败", ex); 31  } 32 return null; 33 }