1 /*
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30  */
31 
32 package org.jf.dexlib2.util;
33 
34 import com.google.common.base.Predicate;
35 import org.jf.dexlib2.AccessFlags;
36 import org.jf.dexlib2.iface.Method;
37 import org.jf.dexlib2.iface.reference.MethodReference;
38 
39 import javax.annotation.Nonnull;
40 import javax.annotation.Nullable;
41 import java.util.Collection;
42 
43 public final class MethodUtil {
44     private static int directMask = AccessFlags.STATIC.getValue() | AccessFlags.PRIVATE.getValue() |
45             AccessFlags.CONSTRUCTOR.getValue();
46 
47     public static Predicate<Method> METHOD_IS_DIRECT = new Predicate<Method>() {
48         @Override public boolean apply(@Nullable Method input) {
49             return input != null && isDirect(input);
50         }
51     };
52 
53     public static Predicate<Method> METHOD_IS_VIRTUAL = new Predicate<Method>() {
54         @Override public boolean apply(@Nullable Method input) {
55             return input != null && !isDirect(input);
56         }
57     };
58 
isDirect(@onnull Method method)59     public static boolean isDirect(@Nonnull Method method) {
60         return (method.getAccessFlags() & directMask) != 0;
61     }
62 
isStatic(@onnull Method method)63     public static boolean isStatic(@Nonnull Method method) {
64         return AccessFlags.STATIC.isSet(method.getAccessFlags());
65     }
66 
isConstructor(@onnull MethodReference methodReference)67     public static boolean isConstructor(@Nonnull MethodReference methodReference) {
68         return methodReference.getName().equals("<init>");
69     }
70 
getParameterRegisterCount(@onnull Method method)71     public static int getParameterRegisterCount(@Nonnull Method method) {
72         return getParameterRegisterCount(method, MethodUtil.isStatic(method));
73     }
74 
getParameterRegisterCount(@onnull MethodReference methodRef, boolean isStatic)75     public static int getParameterRegisterCount(@Nonnull MethodReference methodRef, boolean isStatic) {
76         return getParameterRegisterCount(methodRef.getParameterTypes(), isStatic);
77     }
78 
getParameterRegisterCount(@onnull Collection<? extends CharSequence> parameterTypes, boolean isStatic)79     public static int getParameterRegisterCount(@Nonnull Collection<? extends CharSequence> parameterTypes,
80                                                 boolean isStatic) {
81         int regCount = 0;
82         for (CharSequence paramType: parameterTypes) {
83             int firstChar = paramType.charAt(0);
84             if (firstChar == 'J' || firstChar == 'D') {
85                 regCount += 2;
86             } else {
87                 regCount++;
88             }
89         }
90         if (!isStatic) {
91             regCount++;
92         }
93         return regCount;
94     }
95 
getShortyType(CharSequence type)96     private static char getShortyType(CharSequence type) {
97         if (type.length() > 1) {
98             return 'L';
99         }
100         return type.charAt(0);
101     }
102 
getShorty(Collection<? extends CharSequence> params, String returnType)103     public static String getShorty(Collection<? extends CharSequence> params, String returnType) {
104         StringBuilder sb = new StringBuilder(params.size() + 1);
105         sb.append(getShortyType(returnType));
106         for (CharSequence typeRef: params) {
107             sb.append(getShortyType(typeRef));
108         }
109         return sb.toString();
110     }
111 
MethodUtil()112     private MethodUtil() {}
113 }
114