名字、身份证号校验；浮点数据精确度限制小工具整理

因为eclipse很方便可以看到结果，这次就用了eclipse

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1、名字匹配：如果名字有英文、符号、空格，都会被检验出不规范

    /**
 * 汉字的正则
 */
public static final String nickNameRegular = "^[\\u4E00-\\u9FA5]+$";

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2、身份证校验
首先，创建工具类：IDCardUtils

import java.util.HashMap;

/**
 * 身份证号码校验工具
 */
public class IDCardUtils {

private String _codeError;

// wi =2(n-1)(mod 11)
final int[] wi = { 7, 9, 10, 5, 8, 4, 2, 1, 6, 3, 7, 9, 10, 5, 8, 4, 2, 1 };
// verify digit
final int[] vi = { 1, 0, 'X', 9, 8, 7, 6, 5, 4, 3, 2 };
private int[] ai = new int[18];
private static String[] _areaCode = { "11", "12", "13", "14", "15", "21", "22", "23", "31", "32", "33", "34", "35",
"36", "37", "41", "42", "43", "44", "45", "46", "50", "51", "52", "53", "54", "61", "62", "63", "64", "65",
"71", "81", "82", "91" };
private static HashMap<String, Integer> dateMap;
private static HashMap<String, String> areaCodeMap;

static {
        dateMap = new HashMap<String, Integer>();
        dateMap.put("01", 31);
        dateMap.put("02", null);
        dateMap.put("03", 31);
        dateMap.put("04", 30);
        dateMap.put("05", 31);
        dateMap.put("06", 30);
        dateMap.put("07", 31);
        dateMap.put("08", 31);
        dateMap.put("09", 30);
        dateMap.put("10", 31);
        dateMap.put("11", 30);
        dateMap.put("12", 31);
        areaCodeMap = new HashMap<String, String>();
for (String code : _areaCode) {
            areaCodeMap.put(code, null);
        }
    }

// 验证身份证位数,15位和18位身份证
public boolean verifyLength(String code) {
int length = code.length();
if (length == 15 || length == 18) {
return true;
        } else {
            _codeError = "错误：输入的身份证号不是15位和18位的";
return false;
        }
    }

// 判断地区码
public boolean verifyAreaCode(String code) {
        String areaCode = code.substring(0, 2);
// Element child= _areaCodeElement.getChild("_"+areaCode);
if (areaCodeMap.containsKey(areaCode)) {
return true;
        } else {
            _codeError = "错误：输入的身份证号的地区码(1-2位)[" + areaCode + "]不符合中国行政区划分代码规定(GB/T2260-1999)";
return false;
        }
    }

// 判断月份和日期
public boolean verifyBirthdayCode(String code) {
// 验证月份
        String month = code.substring(10, 12);
boolean isEighteenCode = (18 == code.length());
if (!dateMap.containsKey(month)) {
            _codeError = "错误：输入的身份证号" + (isEighteenCode ? "(11-12位)" : "(9-10位)") + "不存在[" + month
                    + "]月份,不符合要求(GB/T7408)";
return false;
        }
// 验证日期
        String dayCode = code.substring(12, 14);
        Integer day = dateMap.get(month);
        String yearCode = code.substring(6, 10);
        Integer year = Integer.valueOf(yearCode);

// 非2月的情况
if (day != null) {
if (Integer.valueOf(dayCode) > day || Integer.valueOf(dayCode) < 1) {
                _codeError = "错误：输入的身份证号" + (isEighteenCode ? "(13-14位)" : "(11-13位)") + "[" + dayCode
                        + "]号不符合小月1-30天大月1-31天的规定(GB/T7408)";
return false;
            }
        }
// 2月的情况
else {
// 闰月的情况
if ((year % 4 == 0 && year % 100 != 0) || (year % 400 == 0)) {
if (Integer.valueOf(dayCode) > 29 || Integer.valueOf(dayCode) < 1) {
                    _codeError = "错误：输入的身份证号" + (isEighteenCode ? "(13-14位)" : "(11-13位)") + "[" + dayCode + "]号在"
                            + year + "闰年的情况下未符合1-29号的规定(GB/T7408)";
return false;
                }
            }
// 非闰月的情况
else {
if (Integer.valueOf(dayCode) > 28 || Integer.valueOf(dayCode) < 1) {
                    _codeError = "错误：输入的身份证号" + (isEighteenCode ? "(13-14位)" : "(11-13位)") + "[" + dayCode + "]号在"
                            + year + "平年的情况下未符合1-28号的规定(GB/T7408)";
return false;
                }
            }
        }
return true;
    }

// 验证身份除了最后位其他的是否包含字母
public boolean containsAllNumber(String code) {
        String str = "";
if (code.length() == 15) {
            str = code.substring(0, 15);
        } else if (code.length() == 18) {
            str = code.substring(0, 17);
        }
char[] ch = str.toCharArray();
for (int i = 0; i < ch.length; i++) {
if (!(ch[i] >= '0' && ch[i] <= '9')) {
                _codeError = "错误：输入的身份证号第" + (i + 1) + "位包含字母";
return false;
            }
        }
return true;
    }

public String getCodeError() {
return _codeError;
    }

// 验证身份证
public boolean verify(String idcard) {
        _codeError = "";
// 验证身份证位数,15位和18位身份证
if (!verifyLength(idcard)) {
return false;
        }
// 验证身份除了最后位其他的是否包含字母
if (!containsAllNumber(idcard)) {
return false;
        }

// 如果是15位的就转成18位的身份证
        String eifhteencard = "";
if (idcard.length() == 15) {
            eifhteencard = uptoeighteen(idcard);
        } else {
            eifhteencard = idcard;
        }
// 验证身份证的地区码
if (!verifyAreaCode(eifhteencard)) {
return false;
        }
// 判断月份和日期
if (!verifyBirthdayCode(eifhteencard)) {
return false;
        }
// 验证18位校验码,校验码采用ISO 7064：1983，MOD 11-2 校验码系统
if (!verifyMOD(eifhteencard)) {
return false;
        }
return true;
    }

// 验证18位校验码,校验码采用ISO 7064：1983，MOD 11-2 校验码系统
public boolean verifyMOD(String code) {
        String verify = code.substring(17, 18);
if ("x".equals(verify)) {
            code = code.replaceAll("x", "X");
            verify = "X";
        }
        String verifyIndex = getVerify(code);
if (verify.equals(verifyIndex)) {
return true;
        }
// int x=17;
// if(code.length()==15){
// x=14;
// }
        _codeError = "错误：输入的身份证号最末尾的数字验证码错误";
return false;
    }

// 获得校验位
public String getVerify(String eightcardid) {
int remaining = 0;

if (eightcardid.length() == 18) {
            eightcardid = eightcardid.substring(0, 17);
        }

if (eightcardid.length() == 17) {
int sum = 0;
for (int i = 0; i < 17; i++) {
                String k = eightcardid.substring(i, i + 1);
                ai[i] = Integer.parseInt(k);
            }

for (int i = 0; i < 17; i++) {
                sum = sum + wi[i] * ai[i];
            }
            remaining = sum % 11;
        }

return remaining == 2 ? "X" : String.valueOf(vi[remaining]);
    }

// 15位转18位身份证
public String uptoeighteen(String fifteencardid) {
        String eightcardid = fifteencardid.substring(0, 6);
        eightcardid = eightcardid + "19";
        eightcardid = eightcardid + fifteencardid.substring(6, 15);
        eightcardid = eightcardid + getVerify(eightcardid);
return eightcardid;
    }

}

使用：

    String id = "";

if (!new IDCardUtils().verify(id)) {
        System.out.println("身份证号不对");
    } else {
        System.out.println("身份证号正确");
    }

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3、浮点数据精确度限制：

import java.text.DecimalFormat;

public class Demo2 {

public static void main(String[] args) {

float f1 = 1;
float f2 = 2f;
float f3 = 3.0f;
float f4 = 4.32f;
float f5 = 5.4321f;
float f6 = 5.4351f;
float f7 = 5.789f;

double d1 = 1;
double d2 = 2d;
double d3 = 3.0d;
double d4 = 4.32d;
double d5 = 5.4321d;
double d6 = 5.4351d;
double d7 = 5.789d;

        System.out.println("f1---" + getNumAccuracy(f1));
        System.out.println("f2---" + getNumAccuracy(f2));
        System.out.println("f3---" + getNumAccuracy(f3));
        System.out.println("f4---" + getNumAccuracy(f4));
        System.out.println("f5---" + getNumAccuracy(f5));
        System.out.println("f6---" + getNumAccuracy(f6));
        System.out.println("f7---" + getNumAccuracy(f7));

        System.out.println("-----------------------------");

        System.out.println("d1---" + getNumAccuracy(d1));
        System.out.println("d2---" + getNumAccuracy(d2));
        System.out.println("d3---" + getNumAccuracy(d3));
        System.out.println("d4---" + getNumAccuracy(d4));
        System.out.println("d5---" + getNumAccuracy(d5));
        System.out.println("d6---" + getNumAccuracy(d6));
        System.out.println("d7---" + getNumAccuracy(d7));

    }

/**
 * 数字精确度
 */
public static String getNumAccuracy(float f) {

// 构造方法的字符格式这里如果小数不足2位,会以0补足.
        DecimalFormat decimalFormat = new DecimalFormat(".00");
// format 返回的是字符串
        String result = decimalFormat.format(f);
return result;

    }

/**
 * 数字精确度
 */
public static String getNumAccuracy(double d) {

// 构造方法的字符格式这里如果小数不足2位,会以0补足.
        DecimalFormat decimalFormat = new DecimalFormat(".00");
// format 返回的是字符串
        String result = decimalFormat.format(d);
return result;

    }

}

结果：注意数据6和7，带有四舍五入功能

f1---1.00
f2---2.00
f3---3.00
f4---4.32
f5---5.43
f6---5.44
f7---5.79
-----------------------------
d1---1.00
d2---2.00
d3---3.00
d4---4.32
d5---5.43
d6---5.44
d7---5.79