我是Spring MVC的新手，我正在尝试使用AJAX将数据发送到Spring-MVC Controller，点击按钮。我已经编写了这段代码（如下所示），但我得到错误而不是成功。请告诉我们可能出现什么问题？
AJAX：
package cherries;
import java.util.Arrays;
import java.util.Random;
//import strings.ToString;
//import timers.YTimer;
public class AdaAndCherries {
public static void printTable(long[] table, int ySize) {
for (int i = 0; i < table.length; i++) {
//System.out.format("%s ", ToString.toBinaryString(table[i]));
if ((i + 1) % ySize == 0)
System.out.println();
}
}
public static void fillRand(int[] pairs) {
Random r = new Random(System.currentTimeMillis());
int n = pairs.length;
for (int i = 0; i < n;) {
pairs[i++] = r.nextInt(n);
pairs[i++] = r.nextInt(n);
}
}
public static void toTables(long[] tables, int pairs[], int rowSize) {
for (int i = 0; i < pairs.length; i += 2) {
int i2 = i + 1;
int from = pairs[i];
int to = pairs[i2];
// index = starting index of a table + offset, where offset = to/64
int tablesIndex = from * rowSize + (to >> 6);
int shift = to & 63; // offset inside a long digit is to % 64
long bit = 1L << shift;
tables[tablesIndex] |= bit;
// and the same for the table of another node, since graph is bidirectional:
tablesIndex = to * rowSize + (from >> 6);
shift = from & 63;
bit = 1L << shift;
tables[tablesIndex] |= bit;
}
}
public static void main(String[] args) {
int m = 10 * 1000;
int n = m * 2; // in worst case, n = 2*m
// array containing entries like
// [0,1,0,2,2,1,0,3,1,4,5,3
int[] pairs = new int[n];
// each node will have lookuptable of booleans, representing ajancted edge
// this has slightly weird format like
// 0: [0,1,2,3,0...]
// 1: [0,1,2,4,0...]
// 2: [0,1,2,0,0...]
// this tables, each length of 'nodeLookupSize', are concatenated in
a 1d array
// and COMPRIMED AS BOOLEAN FLAGS, each long value has 64 flags
// then looking for cherries is finding differences between two arrays of flags,
// means XORing them:
// [0,1,1,1,0...] (for [0,1,2,3,0...])
// [0,1,1,0,1...] (for [0,1,2,4,0...])
// [0,0,0,1,1,0...] then count ones.
// means 2 cherries found (0,1,3) and (0,1,4) and thats all where node 0
// participates
// after checking pairs 0-1,0-2,0-, the node 0 is done, and must be masked out
// for further pairs like 1-2, etc...
// each row begins from j+1 position, means for 0-3 from position 4,
// because nodes before were already handled,
// because I XOR over length ~n and ~1+2+...n ~ n^2 times, the
algo has O(n^3)
// complexity
// but because not all nodes are connected to each other, i do less XOR's
int rowSize = n / 64 + ((n % 64 == 0) ? 0 : 1);
int allSize = n * rowSize;
System.out.println("size of lookup table of booleans is : " + allSize + " long values what is "
+ (allSize * 8.0) / 1024 / 1024 + " mb, with length of each table in:" + rowSize
+ " long values of size " + rowSize * 8 + " bytes");
long[] tables = new long[allSize];
Arrays.fill(tables, 0);
//YTimer timer = new YTimer();
//timer.start();
// use checks from the page
int[] small = { 0, 1, 0, 2, 2, 1, 0, 3, 1, 4, 5, 3 }; // must be 5 cherries
// small = new int []{ 1, 2, 1, 3, 1, 4, 1,0};// must be 6 cherries
// small = new int []{ 1, 2, 3,2}; // must be 1 cherry
System.arraycopy(small, 0, pairs, 0, small.length);
// fill pairs with random nodes in random order
fillRand(pairs);
// timer.stopAndPrint("pairs initiaded in:");
// fill lookup tables from the pair list:
// timer.start();
toTables(tables, pairs, rowSize);
// timer.stopAndPrint("tables filled in:");
// printTable(tables,rowSize);
// timer.stopAndPrint("rowSize:" + rowSize);
int allCherriesCount = 0;
int n_m_1 = n - 1;
// timer.start();
for (int i = 0, tableStart = 0; i < n_m_1; i++, tableStart += rowSize) {
// System.arraycopy(tables, tableStart, v1Backup, 0, rowSize);
int summ = 0;
int tableStart2Base = tableStart + rowSize;
for (int j = i + 1, tableStart2 = tableStart2Base; j < n_m_1; j++, tableStart2 += rowSize) {
int tablesIndex = tableStart + (j >> 6);
int shift = j & 63;
long bit = 1L << shift;
// true, if i is connected to j:
boolean isConnected = (tables[tablesIndex] & bit) != 0;
if (isConnected) {
// System.arraycopy(tables, tableStart2, v2Backup, 0, rowSize);
// System.out.println( "connected: " + i + " : " + j);
int jNext = j + 1;
int kBegin = jNext >> 6;
int kMaskShift = jNext & 63;
// System.out.println( "kBegin: " + kBegin + ", kMaskShift: " + kMaskShift);
long kMaskBit = ~((1L << kMaskShift) - 1);
// get first long value:
long xor = tables[tableStart + kBegin] ^ tables[tableStart2 + kBegin];
// apply the mask:
xor &= kMaskBit;
summ += Long.bitCount(xor);
// System.out.println( "first xor is:" + ToString.toBinaryString(xor));
kBegin++;
for (int k = kBegin; k < rowSize; k++) {
xor = tables[tableStart + k] ^ tables[tableStart2 + k];
// System.out.println( "next xor is:" + ToString.toBinaryString(xor));
summ += Long.bitCount(xor);
}
}
} // end of iterating over an ajancted list
// cherriesHisto[i] = summ; // also you could fill histo for fun
allCherriesCount += summ;
} // end of main loop.
// timer.stopAndPrint("cherries found:" + allCherriesCount);
System.out.println("cherries found:" + allCherriesCount);
}
JAVA
function add() {
var name = $('#name').val();
$.ajax({
url : "/addUser",
data : name,
type : "POST",
async: false,
success : function(response) {
alert( response );
},
error : function() {
alert("error....");
}
});
}