code: public static URLEncoder createQuery() {
  		final URLEncoder encoder = new URLEncoder();
  		// Special encoding for space
  		encoder.setEncodeSpaceAsPlus(true);
  		// Alpha and digit are safe by default
  		// Add the other permitted characters
  		encoder.addSafeCharacter('*');
  		encoder.addSafeCharacter('-');
  		encoder.addSafeCharacter('.');
  		encoder.addSafeCharacter('_');
  		encoder.addSafeCharacter('=');
  		encoder.addSafeCharacter('&');
  
  		return encoder;
  	}
docs: 创建用于查询语句的{@link URLEncoder}<br>
  编码器针对URI路径编码，定义如下：
  
  <pre>
  0x20 ' ' =》 '+'
  0x2A, 0x2D, 0x2E, 0x30 to 0x39, 0x41 to 0x5A, 0x5F, 0x61 to 0x7A as-is
  '*', '-', '.', '0' to '9', 'A' to 'Z', '_', 'a' to 'z' Also '=' and '&' 不编码
  其它编码为 %nn 形式
  </pre>
  
  详细见：https://www.w3.org/TR/html5/forms.html#application/x-www-form-urlencoded-encoding-algorithm
  
  @return {@link URLEncoder}