获取两个字符串中最大相同子串。比如：
str1 = “abcwerthelloyuiodefabcdef”;str2 = “cvhellobnm”

public String getMaxSameString(String str1,String str2){if(str1 != null && str2 != null){String maxStr = (str1.length() >= str2.length())? str1 : str2;String minStr = (str1.length() < str2.length())? str1 : str2;int length = minStr.length();for(int i = 0;i < length;i++){for(int x = 0,y = length - i;y <= length;x++,y++){String subStr = minStr.substring(x,y);if(maxStr.contains(subStr)){return subStr;}}}}return null;}// 如果存在多个长度相同的最大相同子串// 此时先返回String[]，后面可以用集合中的ArrayList替换，较方便public String[] getMaxSameString1(String str1, String str2) {if (str1 != null && str2 != null) {StringBuffer sBuffer = new StringBuffer();String maxString = (str1.length() > str2.length()) ? str1 : str2;String minString = (str1.length() > str2.length()) ? str2 : str1;int len = minString.length();for (int i = 0; i < len; i++) {for (int x = 0, y = len - i; y <= len; x++, y++) {String subString = minString.substring(x, y);if (maxString.contains(subString)) {sBuffer.append(subString + ",");}}
//                System.out.println(sBuffer);if (sBuffer.length() != 0) {break;}}String[] split = sBuffer.toString().replaceAll(",$", "").split("\\,");return split;}return null;}@Testpublic void testGetMaxSameString(){String str1 = "abcwerthello1yuiodefabcdef";String str2 = "cvhello1bnmabcdef";String[] maxSameStrings = getMaxSameString1(str1, str2);System.out.println(Arrays.toString(maxSameStrings));}