1.在一些字符串?dāng)?shù)組中，常會有重復(fù)的記錄，比如手機(jī)號碼，我們可以通過Hashtable來對其進(jìn)行過濾

public String[] checkArray(String[] str)...{
Hashtable<String, String> hash=new Hashtable<String, String>();

for(int i=0;i<str.length;i++)...{
if(!hash.containsKey(str[i])) //測試指定對象是否為此哈希表中的鍵
hash.put(str[i], str[i]);
}

Enumeration enumeration=hash.keys(); //返回此哈希表中的鍵的枚舉
String[] str_new=new String[hash.size()];
int i=0;

while(enumeration.hasMoreElements())...{
str_new[i]=enumeration.nextElement().toString();
i++;
}
return str_new;
}
示例：
String[] mobile={"13811071500","13811071500","13811071501","13811071503","13811071501"};
mobile=checkArray(mobile);
for(int i=0;i<mobile.length;i++)
System.out.println(mobile[i]);
輸出結(jié)果為：
13811071503
13811071501
13811071500

　　2.A,B均為字符串?dāng)?shù)組，找出在A中存在，而在B中不存在的字符串
public String[] compareArray(String[] A,String[] B){
Hashtable<String, String> hash=new Hashtable<String, String>();
Hashtable<String, String> hash_new=new Hashtable<String, String>();

for(int i=0;i<B.length;i++)
hash.put(B[i], B[i]);

for(int i=0;i<A.length;i++){
if(!hash.containsKey(A[i]))
hash_new.put(A[i], A[i]);
}

String[] C=new String[hash_new.size()];
int i=0;
Enumeration enumeration=hash_new.keys();

while(enumeration.hasMoreElements()){
C[i]=enumeration.nextElement().toString();
i++;
}
return C;
}
示例：
String[] mobile1={"13811071500","13811071501","13811071502","13811071503","13811071504"};
String[] mobile2={"13811071500","13811071505","13811071502","13811071506","13811071504"};
String[] mobile3=compareArray(mobile1,mobile2);
for(int i=0;i<mobile3.length;i++)
System.out.println(mobile[i]);
輸出結(jié)果：
13811071503
13811071501
存在的問題：
每次都是倒序，可以再對程序稍加改動，變成正序。

　　3.將一個字符串?dāng)?shù)組中某一個特定的字符串過濾掉

/** *//**檢驗(yàn)一個字符串?dāng)?shù)組，若包含某一特定的字符串，則將該字符串從數(shù)組中刪
除，返回剩余的字符串?dāng)?shù)組
* @param str_array 字符串?dāng)?shù)組
* @param str_remove 待刪除的字符串
* @return 過濾后的字符串
*/
public String[] removeStrFromArray(String[] str_array,String
str_remove)...{
Hashtable<String, String> hash=new Hashtable<String, String>();
for(int i=0;i<str_array.length;i++)...{
if(!str_array[i].equals(str_remove))
hash.put(str_array[i], str_array[i]);
}
//生成一個新的數(shù)組
String[] str_new=new String[hash.size()];
int i=0;
Enumeration enumeration=hash.keys();
while(enumeration.hasMoreElements())...{
str_new[i]=enumeration.nextElement().toString();
i++;
}
return str_new;
}