推断字符串string是数字、json结构、xml结构

import org.json.JSONException;
import org.json.JSONObject;
import org.dom4j.DocumentException;
import org.dom4j.DocumentHelper; 

public class StringTest { 

/**
* @param args
*/
public static void main(String[] args) {
String string1 = "123";
String string2 = "fdgsewe323";
String string3 = "{/"task/":/"324vfsdfg/"}";
String string4 = "<ww>3243</ww>";
//	System.out.println("string1::number"+isNumber(string1));
//	System.out.println("string2::number"+isNumber(string2));
//	System.out.println("string3::json"+isJson(string3));
//	System.out.println("string4::xml"+isXML(string4));
//	System.out.println("string1::json"+isJson(string1));
//	System.out.println("string2::xml"+isXML(string2));
//	System.out.println("string3::number"+isNumber(string3));
//	System.out.println("string4::xml"+isXML(string4)); 

System.out.println("string1::"+getType(string1));
System.out.println("string2::"+getType(string2));
System.out.println("string3::"+getType(string3));
System.out.println("string4::"+getType(string4));
} 

public static String getType(String string) {
if (isNumber(string))
return "Number";
else if (isJson(string))
return "Json";
else if (isXML(string))
return "xml";
else
return "String";
} 

/**
* 推断字符串是否是数字
*/
public static boolean isNumber(String value) {
return isInteger(value) || isDouble(value);
} 

/**
* 推断字符串是否是整数
*/
public static boolean isInteger(String value) {
try {
Integer.parseInt(value);
return true;
} catch (NumberFormatException e) {
return false;
}
} 

/**
* 推断字符串是否是浮点数
*/
public static boolean isDouble(String value) {
try {
Double.parseDouble(value);
if (value.contains("."))
return true;
return false;
} catch (NumberFormatException e) {
return false;
}
} 

/**
* 推断是否是json结构
*/
public static boolean isJson(String value) {
try {
new JSONObject(value);
} catch (JSONException e) {
return false;
}
return true;
} 

/**
* 推断是否是xml结构
*/
public static boolean isXML(String value) {
try {
DocumentHelper.parseText(value);
} catch (DocumentException e) {
return false;
}
return true;
}
}