如何创建Java包以及如何在另一个包中导入它们？

Question

我是java新手我试图从另一个导入包但另一个不会编译因为它说它找不到第一个包就是我做了：

第一包代码：

package sagar.sql;

import java.sql.Connection;
import java.sql.SQLException;

import oracle.apps.bne.exception.BneException;
import oracle.apps.bne.framework.BneWebAppsContext;
import oracle.apps.bne.utilities.sql.BneBaseSQL;

public class SagarSupplierSiteNameSQL extends BneBaseSQL {
public SagarSupplierSiteNameSQL(BneWebAppsContext paramBneWebAppsContext, 
                                String paramString) throws SQLException, 
                                                           BneException {
    Connection connection = paramBneWebAppsContext.getJDBCConnection();
    StringBuffer stringBuffer = new StringBuffer();

    stringBuffer.append("SELECT PARTY_NAME,ACCOUNT_NUMBER,LOCATION  WHERE org_id = 281 AND ACCOUNT_NUMBER = :1");


    if ((paramString != null) && (!paramString.trim().equals(""))) {
        stringBuffer.append("AND " + paramString);
    }

    //stringBuffer.append(" ORDER BY VENDOR_SITE_CODE, ADDRESS ");

    setQuery(connection, stringBuffer.toString());
  }
}

第二包代码：

package sagar.validator;


 import java.util.Hashtable;

 import oracle.apps.bne.exception.BneException;
 import oracle.apps.bne.exception.BneFatalException;
 import oracle.apps.bne.exception.BneMissingParameterException;
 import oracle.apps.bne.framework.BneWebAppsContext;
 import oracle.apps.bne.integrator.validators.BneUploadValidator;
 import oracle.apps.bne.utilities.sql.BneCompositeSQLCriteria;
 import oracle.apps.bne.utilities.sql.BneResultSet;
 import oracle.apps.bne.utilities.sql.BneSQLStatement;

 import sagar.sql.SagarSupplierSiteNameSQL;

public class SagarSupplierSiteNameValidator extends BneUploadValidator {

public String[] getDomainParameters() {
    return new String[] { "P_CUST_NUM" };
}

public BneResultSet getDomainValues(BneWebAppsContext paramBneWebAppsContext, 
                                    Hashtable paramHashtable, 
                                    BneCompositeSQLCriteria paramBneCompositeSQLCriteria) throws BneException {

    SagarSupplierSiteNameSQL sagarSupplierSiteNameSQL = null;
    BneResultSet bneResultSet = null;
    BneSQLStatement bneSQLStatement1 = new BneSQLStatement();

    if (paramBneCompositeSQLCriteria != null) {
        bneSQLStatement1 = 
                paramBneCompositeSQLCriteria.evaluate(bneSQLStatement1);
    }

    String str1 = (String)paramHashtable.get("P_CUST_NUM");

    if (str1 == null) {
        throw new BneMissingParameterException("Customer Number Field Error");
    }


    try {
        sagarSupplierSiteNameSQL = 
                new SagarSupplierSiteNameSQL(paramBneWebAppsContext, 
                                             bneSQLStatement1.getStatement());
        BneSQLStatement bneSQLStatement2 = 
            new BneSQLStatement(sagarSupplierSiteNameSQL.getQuery(), 
                                new Object[] { str1 });

        bneSQLStatement2.append("", bneSQLStatement1.getBindValues());
        bneResultSet = 
                sagarSupplierSiteNameSQL.getBneResultSet(bneSQLStatement2.getBindValuesAsArray());
    } catch (Exception exception) {
        throw new BneFatalException(exception.toString());
    }


    return bneResultSet;
}


}

终点站：

-bash-3.00$ javac /apps/DEV/apps/apps_st/comn/java/classes   
/SagarSupplierSiteNameSQL.java -d "$JAVA_TOP/sager/sql"
-bash-3.00$     
-bash-3.00$ 
-bash-3.00$ 
-bash-3.00$ 
-bash-3.00$ javac /apps/DEV/apps/apps_st/comn/java/classes   
/SagarSupplierSiteNameValidator.java -d "$JAVA_TOP/sager/validator"
/apps/DEV/apps/apps_st/comn/java/classes   
/SagarSupplierSiteNameValidator.java:15: package sagar.sql does not exist
import sagar.sql.SagarSupplierSiteNameSQL;
            ^
/apps/DEV/apps/apps_st/comn/java/classes   
/SagarSupplierSiteNameValidator.java:27: cannot find symbol
symbol  : class SagarSupplierSiteNameSQL
location: class sagar.validator.SagarSupplierSiteNameValidator
    SagarSupplierSiteNameSQL sagarSupplierSiteNameSQL = null;
    ^
/apps/DEV/apps/apps_st/comn/java/classes   
/SagarSupplierSiteNameValidator.java:45: cannot find symbol
symbol  : class SagarSupplierSiteNameSQL
location: class sagar.validator.SagarSupplierSiteNameValidator
                new SagarSupplierSiteNameSQL(paramBneWebAppsContext, 
                    ^
`3 errors

如果您需要有关我面临的问题的更多信息，请问我，请帮助我。

Answer 1

由于您使用的是交叉导入，因此这些文件不会单独编译。您必须立即编译所有文件。

此外，您的类不在java文件顶部的包中。从两个文件中删除package sagar.validator;和package sagar.sql;并运行以下命令：

javac /apps/DEV/apps/apps_st/comn/java/*.java

如果你想使用包，请在SagarSupplierSiteNameSQL.java文件夹中移动/apps/DEV/apps/apps_st/comn/java/sagar/sql

在SagarSupplierSiteNameValidator.java内的/apps/DEV/apps/apps_st/comn/java/sagar/validator。

进入/apps/DEV/apps/apps_st/comn/java，以下2个命令中的任何一个都应该有效。

javac  **/*.java 

要么

javac  **/**/*.java

Answer 2

当我使用这两个命令时，它工作得很好：

  javac /apps/DEV/apps/apps_st/comn/java/classes/SagarSupplierSiteNa‌​meSQL.java -d "$JAVA_TOP" 

和

 javac /apps/DEV/apps/apps_st/comn/java/classe/SagarSupplierSiteNa‌meValidator.java -d "$JAVA_TOP" 

它创建了包的目录自动感谢@Pankaj Singhal，因为你的重播引导了我